【摘要】 本试验研究了玉米-豆粕型日粮中添加高剂量不同水平的植酸酶对0～3和4～6周肉鸡养分利用率的影响。选用1日龄AA肉鸡公雏576只,随机分为6组,每组8个重复,每个重复12只。试验日粮分0～3和4～6周两个阶段,6个处理组:正对照组(前期为总磷0.69%,0.45%NPP;后期为总磷0.59%,0.35%NPP);负对照组(前期总磷0.60%,0.35%NPP;后期为总磷0.49%,0.25%NPP);4个试验组在负对照日粮中分别添加500、2000、8000和32000 FTU/kg 4种植酸酶水平。结果显示:①日粮添加高剂量不同水平的植酸酶显著影响生长前期(17～21日龄)肉鸡的钙、磷的消化利用率(P<0.05),随着植酸酶添加水平增加,钙的消化利用率显著增加(P<0.05)。②日粮添加高剂量不同水平的植酸酶显著影响38～42日龄肉鸡磷的消化利用率(P<0.05)。在负对照组日粮中随着植酸酶水平添加的提高,钙的消化利用率呈现先增加后降低的趋势,磷的养分利用率反而显著减少。③日粮添加高剂量不同水平植酸酶显著增加生长前期(17～21日龄)肉鸡的粗蛋白质的消化利用率和表观代谢能(P<0.05),在生长后期(38～42日龄)对肉鸡的粗蛋白质的消化利用率和表观代谢能提高达到显著水平(P<0.05)。因此,高剂量不同水平的植酸酶显著提高肉鸡AME和粗蛋白质、钙、磷的消化利用率,添加高水平植酸酶可以适当调低日粮能量和蛋白质水平,日粮中总磷(tP)水平应低于NRC标准,减少无机磷和钙的添加量,以提高钙、磷在体内的存留量。更多还原

【Abstract】 An experiment was conducted to determine the effect of high levels of microbial phytase supplementation in corn-soy-based diets on nutrient availability of broiler chickens.A totalof 576 one-day old male Arbor Acres broilers were assigned to 6 dietary treatments,consisting of 8 pens of 12 birds each,and were fed two periods experimental diets from 1 to 21 d and 22 to 42 d.The diets include a positive control(0.69% tP,0.45% nonphytate P for 1 to 21 d;0.59% tP,0.35% nonphytate P for 22 to 42 d)and a negative control(0.60% tP,0.35% nonphytate P for 1 to 21 d;0.49% tP,0.25% nonphytate P for 22 to 42 d),and 4 more negative diets with 500,2000,8000,32000 FTU/kg phytase.The results showed that ① High dose of phytase could significantly improve the availability of Ca at 17 to 21 d(P <0.05).②High dose of phytase could significantly influence the availability of P at 38 to 42 d(P<0.05),with the phytase levels increasing,the availability of P significantly decreased,while the availability of Ca tended to be increased then to be decreased.③There were significantly improvements in availability of crude protein and AME with phytase levels increasing(P<0.05)either at 17 to 21 d or at 38 to 42 d.This study suggest that higher levels of phytase can be used to improve the overall utilization of phytate P and possibly other nutrients in a tP-deficient diet.That current phytase supplementation and diet nutrients within the poultry industry may need to be reevaluated.更多还原