Broiler Performance in Response to Phytate and Supplemented Phytase

Abstract

Phosphorus (P) is a macro mineral in broiler nutrition. In growing broilers, besides its requirement for proper bone development, it is also involved in almost all metabolic processes. Poor P availability results in decreased productivity and poor health status.Phosphorus availability from plant derived feeds is affected by an anti-nutritional factor “phytate", which forms a variety of insoluble salts with most of the minerals including P, calcium (Ca), magnesium, zinc (Zn) and copper (Cu) due to its reactive anion capability. So, phytate is responsible for considerable nutrient losses as vegetable sources form a major portion in broiler diet formulations. Phytate has also been reported to form complexes with protein and proteolytic enzymes (pepsin and trypsin). Mono-gastric animals lack endogenous phytase (an enzyme capable of hydrolyzing phytate bound P, Ca, protein and other nutrients), so phytate decreases the nutrient availability at the intestinal level in poultry. Application of phytase in poultry rations may liberate cations and other nutrients bound by phytate-P complexes resulting in improved production parameters and body structure characteristics in broilers. However, efficacy of supplemental phytase rests on its rate of application, Ca: P in ration, composition of diet, genotype and age of birds. Phytase could ensure the economical poultry production by the exploitation of inherent nutritional potential of feedstuffs. Some studies, however, showed that phytase does not degrade dietary phytate efficiently and thus the negative influence of phytate on protein digestibility is not completely removed by phytase supplementation. More focused researchon currently available phytase feed enzymes and their potentialimproved action by the simultaneous use of other exogenous enzymes, which complement their activity is recommended.