Effect of dietary phosphorus level and phytase inclusion on weaner pig performance and subsequent bone development

Abstract A 3 × 2 factorial experiment was used to evaluate the response of weaner pigs (11 kg in body weight) to 3 concentrations of dietary phosphorus ( P ) (4.5, 5.5 and 6.4 g/kg total P ) and 2 concentrations of phytase (0 and 500 FTU/kg) on pig performance, faecal score and bone development (8 replicates/treatment, 2 pigs/replicate = 96 pigs). Bone samples were collected from 48 pigs (8/treatment) at the end of the weaner performance study (30 kg body weight). The remaining 48 pigs were then offered a commercial grower and finisher diet with 6 and 5.5 g/kg P respectively until slaughter at 100 kg. In the weaner pig performance study faecal score was decreased as the dietary P concentration decreased ( P P P concentrations ( P P concentration increased. Offering diets with phytase ( P P concentration ( P Ca and P concentrations. In conclusion, the inclusion of phytase in weaner pig diets may alleviate the use of high P diets. There was no performance advantage to feeding high P diets during the weaner stage; however feeding a high P diet resulted in the pig at 100 kg body weight having increased bone ash, Ca and P concentrations.