Effect of phytase on P and Ca utilization at different age periods of laying hens fed higher amount of rapeseed meal

Abstract

The aim of the present research was to determine the content of phytate phosphorus in rapeseed meal and to evaluate the effects of exogenous enzyme (phytase) on the utilization of phosphorus (P) and calcium (Ca) by laying hens. The chemical analyses of rapeseed meal used in the further test with laying hens showed it to contain a very significantly high level of phytate-P (8.61 mg/g dry mass, DM) – about 77% DM of the total P in the form of phytate-P. The results of the metabolic test with Lohmann LSL hens between 33 and 42 wk of age fed diets with a different content of available P (0.20–0.40%) and with a higher content of rapeseed meal indicated the phytase (produced from fungus Pheniophora lycii) additives to improve digestibility of both P and Ca in particular. Dietary P concentration had a positive influence on the digestibility of Ca (P <0.05). It allows not only reducing a dietary P level, but also significantly savin on feed cost. Keywords: laying hens, rapeseed meal, phytase, phosphorus, calcium, utilization