ECOLOGICAL IMPLICATIONS OF PHYTASE ADDED TO NORMAL AND DEFICIENT AVAILABLE PHOSPHORUS DIETS OF LAYING HENS MEASURED BY N AND P EXCRETION

Ragip Kastrati, Skender Muji, Nuridin Mestani, Alltane Kryeziu, Muhamet Kamberi

Abstract: Nitrogen and phosphorus are two main pollutants responsible for environmental eutrophication, a process of saturation of surface water with nutrients which as a result of oxygen depletion favors overgrowth of algae and grazing bacteria. An experiment was conducted to determine the effects of adding phytase to a corn-soybean meal laying hen diet over 8 weeks with different available phosphorus (AP) levels on total nitrogen (TN) and total phosphorus (TP) in excreta. In the experiment, 144 Hisex Brown hens were fed two levels of AP (0.12% and 0.46%) and two levels of phytase (0, and 600 Phytase Units-FTU)/kg). In the experiment supplemental phytase resulted in lower total excreta nitrogen (1.50 ± 0.04; 1.23 ± 0.04; 133 ± 0.07; and 1.31 ± 0.04%, for hens fed 0.12% AP–phytase, 0.12% AP + phytase, 0.46% AP - phytase, and 0.46% AP + phytase, respectively) and total excreta phosphorus (1.14 ± 0.01; 1.03 ± 0.05; 1.34 ± 0.03; and 1.37 ± 0.01, respectively). Results of this study indicate that 600 FTU added to corn soybean meal based layer diets containing 0.12% AP contributes to significantly lower
levels of total excreta nitrogen and phosphorus without any adverse effects on the performance of laying hens.

Keywords: excreta; laying hens; nitrogen; phosphorus; phytase

Date published: 2017-09-08