Effect of feed supplementation with phytase on phosphorus utilization by piglets

A series of digestion-balance experiments were carried out with the aim to determine the in fluence of the incorporation of phytase (1250 U/kg) on pho sphorus apparent digestibility and retention in piglets. The experimental m aterial comprised hogs of 30 kg mean body weight which were divided into 7 groups of 5 animals each and fed diets containing high proportions of the f ollowing experimental feeds: barley, wheat or rapeseed meal (RSM). During t he experiment, phosphorus apparent digestibility and retention for diets co ntaining the examined feeds were determined by direct methods. Moreover, in directly; phosphorus digestibility in barley, wheat and RSM was also ascert ained. It was established that phosphorus apparent digestibility coefficients for diets containing barley and wheat were similar and, on average, reached 51 %. Diet supplementation with phytase was found to have a significant effect (P < 0.05) on the improvement of phosphorus apparent digestibility and ret ention. Phytase was found to be least effective when added to diets contain ing RSM. Phosphorus contained in barley was digested by 53 %, while that by wheat - in 59 %. The addition of phytase improved significantly (P < 0.05) the phos phorus apparent digestibility coefficients in these feeds by 16.2 and 14.0 percentage points, respectively. On the other hand, phosphorus digestibilit y coefficient in RSM was 41.6 % and phytase increased its value only by 4.1 %.