Study effects of QPT2-phytases on P-Digestibility in growing turkeys

Growing turkeys are, like other poultry species, very restricted in utilising phytate P in cases when diets do not contain the enzyme phytase. Microbial phytases can improve the utilisation of phytate P. Additionally it is known that various phytase preparations may affect the utilisation of phytate P to a different extent, caused by differences in their in vitro characteristics such as pH range or resistance against proteolytic enzymes. In plant-based diets, the use of inorganic phosphate salts can be reduced in cases when microbial phytase is supplemented. This replacement depends on the product specific efficiency in releasing P under in vivo conditions. This is one reason why the efficiency of phytases needs to be determined in balance experiments. Therefore this experiment was designed to study the efficiency of two phytase preparations in growing turkeys. P utilisation at marginal P supply, generally considered the most sensitive parameter for the efficiency of phytase, was determined based on quantitative excreta collection