Body weight gain and nutrient utilization in starter pigs that are liquid-fed high-moisture corn-based diets supplemented with phytase

A total of 384 starter pigs were used to examine the application of exogenous phytase in high-moisture corn (HMC)-based liquid diets. Pigs were randomly assigned to 24pens in six blocks. Pens were randomly assigned one of four HMC-based diets formulated to vary in total phosphorus (P) content (Low, Medium and High), with phytase added to only the Low P diet (Phy). Body weight gain and feed intake were monitored until body weight exceeded 20 kg. Apparent total tract digestibility of crude protein and P were measured on day 21 (Phase II) and day 42 (Phase III). At the end of the trial, two pigs from each pen were sacrificed for analysis of carcass composition and evaluation of metacarpals. Pigs fed the Phy treatment had increased digestibility of crude protein (P0.05). In conclusion, performance of starter pigs fed liquid HMC-based diets was maintained at dietary P levels below established requirements, but addition of phytase improved bone strength and mineralization. This study provides evidence for the effectiveness of phytase, and that P requirement for maximum rate of weight gain in pigs is not sufficient for maximum skeletal development