EFFECT OF PHYTASE SUPPLEMENTATION TO BARLEY-CANOLA MEAL AND BARLEY-SOYBEAN MEAL DIETS ON PHOSPHORUS AND CALCIUM BALANCE IN GROWING PIGS

Abstract

Two metabolism experiments were carried out, to determine the effect of microbial phytase addition to barley-canola meal and barley-soybean meal diets on P and Ca balance in growing. pigs; In experiment 1, six barrows (29.6kg: initial LW) were fed a barley-canola meal diet, without or. with phytase (500 units.kg(-1) ring 24 days, according to a crossover design. The diet provided suboptimal levels. of P. In experiment 2, twelve barrows (53.4kg initial LW) were fed four barley-soybean meal diets, according to a two-period changeover design; Diet 1 was supplemented with inorganic P and Ca to meet requirements,. diets, 2, 3 and 4 contained suboptimal levels of P, diet 3 being supplemented with phytase; diet 4 was supplemented with both phytase and a mixture of xylanase and beta-glucanase. The supplementation of phytase to the barley-canola meal and the barley-soybean meal diets increased (P0.05) values far P retention and P and Ca digestibilities as for diets 1 and 3. In conclusion; phytase supplementation to the barley-canola meal and barley-soybean meal diets improved the utilization of P and digestibility of Ca; but no further effect was observed with the supplementation with the mixture of xylanase and beta-glucanase.