Effect of Phytase Derived from the E. coli AppA Gene on Weaned Piglet Performance, Apparent Total Tract Digestibility and Bone Mineralization

Simple Summary Plants store phosphorus mainly in a form that is indigestible to pigs: phytate. Unabsorbed minerals excreted into the environment are considered to be environmental pollutants. Our study focuses on the effects of novel types of phytase enzymes in diets deficient in external phosphorus on the performance, digestibility of crude protein, dry matter and minerals, and bone mineralization of weaned piglets. Using novel phytases, we noted a positive impact on body weight gain, feed conversion ratio, the digestibility of phosphorus and calcium, and phosphorus and calcium content in bones. There was no significant improvement in the content of dry matter or digestion of crude protein. This study reveals novel phytases to be useful additives for weaned piglet diets because of their superior performance results and phosphorus absorption. Abstract The objective of this study was to assess the effect of novel appAT1 and appAT2 phytase inclusion at 250 phytase units (FTU)/kg on weaned piglet performance, the apparent total tract digestibility of P and Ca, and bone mineralization. Piglets (48 males) were randomly divided into four treatment groups: a positive control (PC), with recommended levels of phosphorus (P) and calcium (Ca), a negative control (NC) deficient in P and Ca, and two experimental groups with NC diets supplemented with phytase derived from the appA gene of Escherichia coli. Diets fed in a mashed form were divided into prestarter (0-21 days) and starter (22-42 days) periods. During the whole period of the study, the experimental diets improved (p < 0.05) the body weight gain (BWG) and feed conversion ratio (FCR) compared to the NC diet. The apparent total tract digestibility (ATTD) of the dry matter and crude protein was not significantly different among the diets. Phytase-supplemented diets improved the ATTD of P (p < 0.05) and the ATTD of Ca (p < 0.05). Bone ash content in the third metacarpal and P and Ca content were improved among the phytase supplemented diets compared to the NC diet.