اثر فيتاز ميكروبي بر قابليت هضم ظاهري اسيدهاي آمينه و برخي از شاخصهاي عملكرد در جوجه هاي گوشتي نر

Effect of microbial phytase on apparent digestibility of amino acids and performance of male broiler chickens

An experiment was conducted to evaluate the effects of microbial phytase on apparent amino acid and protein digestibility and performance of broiler chicks. Three hundred day-old male chicks of a commercial strain (Ross) were wing banded, weighted and randomly allocated to five treatment groups with five replicates of 12 chicks in each floor pen. The treatments supplemented with 0, 250, 500, 750 and 1000 FTU phytaselkg of diet. The diets contained adequate phosphorus and calcium and were fed to chicks from 0-28 days of age. Excreta was totally collected from 21 to 24 days of the experiment. The excreta stored at -20 C, freeze-dried and analyzed for amino acids. Live body weight, feed intake and feed efficiency were recorded weekly. Microbial phytase had a significant effect (P<0.05) on apparent digestibility of amino acids and protein. Adding 250 and 500 FTU of phytaselkg of diet, significantly increased digestibility of all amino acids (except alanine) and protein. Higher levels of phytase caused poor digestibility compare to 250 and 500 FTU. Phytase had no significant effect (P>0.05) on live body weight, feed intake, feed efficiency and protein efficiency ratio.