Comparative evaluation of the effect of two different phytase enzymes on growth performance of broiler chickens.

Background: The supplementation of phytase enzyme is one of the ways in poultry industry to improve performance, reduce production costs and prevent environmental pollution. The present study aimed to compare the effects of two different commercial phytase, on growth performance of broiler chickens. Methods: ۷۸۴ day old Arbor Acres were randomly allocated to one of ۷ dietary treatments with ۴ replicates (۲۸ birds/rep) in a ۲×۳ factorial design with a control group. Chickens were housed in floor pens and grown for ۴۲ days experimental period. The experimental diets were based on corn-soybean meal and treatments included: ۱) PC, positive control (basal diet with recommended phosphorus and calcium), ۲ and ۳) NC۱ and NC۲, negative controls (basal diet with phosphorus and calcium levels ۲۵ and ۵ percent and ۵۰ and ۱۰ percent lower than the recommended, respectively), and ۴ enzyme treatments, NC۱R, NC۲R and NC۱E, NC۲E, (NC۱ or NC۲ + Ronozyme hiphos, or Ecoenzyme phyt respectively). Average daily feed intake (DFI), daily weight gain (DWG), and feed conversion ratio (FCR) were measured at the end of the starter, grower, and finisher phases and were compared statistically. Results: Low reduction of calcium and phosphorus content in NC۱ treatment diets had no negative effect on mean DWG, DFI and FCR as compared with PC treatment in all phases. However, during the whole experimental period, DWG and DFI were lower in NC۲ and NC۲R groups than those in PC diet (P < ۰.۰۰۰۱). FCR were not affected by the treatment diets. Conclusion: Reduction in the calcium and phosphorus content of diet had a negative effect on performance parameters in NC۲ treatment group but supplementation of phytase enzymes was compensated it. The effects on performance parameters in NC۲E were better than NC۲R enzyme treatment during the whole experimental period.

کلیدواژه ها:

Broiler ، Calcium ، Performance ، Phosphorus ، Phytase