4. Discussion
Swine manure contains high levels of P, the result of poor
digestibility of phytate P and feeding above the P requirement
(Knowlton et al., 2004). Hence, there is a need to reduce the
dietary P level as well as to develop nutritional strategies to
improve the bioavailability of this element. However, such
efforts could result in subtle dietary P deficiencies that not
only affect growth but also adversely affect bone integrity.
The hypothesis of this study was that increasing the inclusion
level of phytase (0, 500, 1000 and 1500 FTU/kg) in a low-P
weaner pig diet (2.2 g aP/kg) from 8 to 33 kg BW will affect
growth performance, mineral retention and bone mineral