Effect of Phytase Addition at Different Levels to Rations Containing Normal and Lower Levels of Available Phosphorus on Performance of Broiler Chicks and Utilization of Phosphorus

Authors : Yilmaz Bahtiyarca, Mehmet Öküz

Pages : 57-71

View : 6 | Download : 20

Publication Date : 1996-12-31

Article Type : Research Paper

Abstract :A study was conducted to determine the effect of adding phytase at different levels on serum phosphorus level (SPL), toe ash (TA) as a measure utilization of phosphorus and performance of broiler chicks fed diets containing normal and lower levels of available phosphorus (AP). Twelve treatments consisting of three levels AP (0.20, 0.35, 0.50%) and four levels phytase (0, 500, 1000, 1500 ünite) in 3x4 factorial arrangement were used with two replicates of the birds each. Total of 240 unsexed chicks were fed with starter diets for firts three weeks and finisher diets during the next three weeks of the experiment. All diets were isocaloric and isonitrogenous. Measured all parameters except feed / gain ratio at six weeks of age when the groups fed diet containing 0.20% AP were significantly lower than that of groups fed with 0.35 or 0.50% AP, but phosphorus levels of ration did not significantly effect the feed / gain ratio. Adding increasing levels of phytase to diets significantly and in quadratic Increased body weight, gain and did not effect feed consumption, feed / gain ratio and TA. Increase in SPL, when the level of added enzyme to ration was increased, was linear, but only chicks fed 1500 ünite phytase (7.52 mg/dl) was signicantly higher (P<0.05) than those fed diet without phytase (4.33 mg/dl). Phytase supplementatin of diet containing 0.20% AP resulted in nonlinear but signifcant increase (P<0.01) in body weight, gain and TA and resulted in linear increase (P<0.05) in SPL. Chicks fed diet containing 0.20% AP without phytase had the lowest values with regard to measured variables compared to other groups. No one measured variables did not significantly effected by adding phytase to diets with 0.35 and 0.50% AP.
Keywords : Broyler, kullanılabilir fosfor, fitaz enzimi