phytase at half the dose in terms of phosphorus and calcium digestibility. In 14 trials with over 550 data points involving both weaner and grower-finisher pigs, using the Buttiauxella phytase instead of a commercial E. coli phytase resulted in a 34% improvement in phosphorus and calcium release and considerable digestible energy improvements (~35 kcal/kg feed (0.15 MJ)). These improvements translated into an economic advantage of around $1.00-1.30/tonne, over E. coli phytase use, even at 500FTU12.