English

Abstract

An experiment was conducted from 1 to 42 day post hatching to determine the effects of a microbial phytase (Natuphos) and glycanase preparations with predominantly xylanase and β-glucanase (Feedzyme) on the performance, serum mineral levels and antibody titer against newcastle disease, of broilers fed nutritionally marginal diets. A completely randomized experimental design was used, and chicks were divided into 5 treatment groups, with 4 replicates per treatment and 10 chicks per replicate. Diets were corn-wheat-soybean meal based with the same nutritional specifications, differing only in the concentration of Ca and nonphytate P (Ca-nPP). Treatments were: (1) diet with the energy of 2900 kcal/kg and 0.63% Ca and 0.28% available P, without enzyme (CTL+);T2) diet with the energy of 2900 kcal/kg and 0.63% Ca and 0.28% available P, without enzyme (CTL−); 3, 4 and 5) diet with the energy of 2900 kcal/kg and lower level of Ca and P (experimental group 2) respectively comprising 600,800,1000 phytase  unit/kg of diet from Natuphous and 42,70,98 Xylanase unit/kg and 60,100,140 β-glucanase unit/kg of diet from feedzyme. Antibody titers against Newcastle disease were increased by incremental phytase and xylanase addition in experiments. These finding indicates that broilers consuming a ME, Ca, P-deficient corn-soybean meal-wheat diet can achieve maximum humoral immunity when phytase, xylanase and β-glucanase is supplemented to 1000, 98 and140 unit/kg diet. Performances of chicks fed with low-Ca-nPP diets plus phytase, xylanase and glucanase were comparable to those obtained with the low-Ca-nPP and adequate-Ca-nPP diets. Enzymes supplementation increased plasma Ca level (P > 0.05) but had no significant effect on plasma P level.   Key words: Phytase, glycanase, newcastle disease, performance, immunity, broiler.