Effects of phytase B on laying performance, eggshell quality and on phosphorus and calcium balance in laying hens fed phosphorus-deficient maize-soybean meal diets
Zyla, K.,University of Agriculture, Cracow (Poland). Dept. of Food Biotechnology | Mika, M.,University of Agriculture, Cracow (Poland). Dept. of Food Biotechnology | Swiatkiewicz, S.,National Research Inst. of Animal Production, Balice (Poland). Dept. of Animal Nutrition and Feed Science | Koreleski, J.,National Research Inst. of Animal Production, Balice (Poland). Dept. of Animal Nutrition and Feed Science | Piironen, J.,AB Enzymes Oy, Rajamaeki (Finland)
A study was conducted to evaluate the effects of dietary supplementation of phytase B (product of the Aspergillus niger phyB gene expressed in Trichoderma reesei) on feed intake, laying performance, eggshell quality, and on phosphorus and calcium balance in laying hens. Seventy-two 40-weeks-old Hy Line Brown hens were fed for 14 weeks the following four phosphorus-deficient (0.12% nonphytate phosphorus, NPP) maize-soybean meal-based diets: (1) calcium-deficient (2.8% Ca) control diet; (2) diet 1 + phytase B at the activity of 2.5 acid phosphatase units (AcPU/kg); (3) control diet (3.8% Ca); (4) diet 3 + phytase B at the activity of 2.5 AcPU/ kg. Each dietary treatment was fed to 18 cages of hens (1 hen/cage). Hens fed the NPP- and Ca-deficient diets consumed more feed (P less than 0.01) and excreted less Ca (P less than 0.01) than those receiving P-deficient diets with the standard Ca level. There were no effects of Ca level on feed utilization, egg mass, egg weight, and eggshell breaking strength. Egg production, although numerically higher in hens fed low Ca diets with no enzyme added, failed to be significantly different due to the low number of hens investigated. Phytase B increased mean egg weight by about 7% in layers fed the NPP- and Ca-deficient diet (Ca x phytase B interaction, P less than 0.05), increased shell breaking strength, particularly at the standard Ca level, significantly enhanced amounts of Ca retained by layers and amounts of P retained by hens fed the Ca-deficient diets. Additionally, phytase B improved Ca retention at both dietary Ca levels and P retention in hens fed the Ca-deficient diets. Results of the study indicate that the efficacy of phytase B in NPP-deficient diets is strongly influenced by the dietary Ca level and the enzyme may modulate egg weight, eggshell quality, P and Ca retention in laying hens fed low-NPP maize-soybean meal-based diets.
Показать больше [+] Меньше [-]Ключевые слова АГРОВОК
Библиографическая информация
Эту запись предоставил Library of Antonin Svehla