植酸酶对肉鸡生产性能及饲料养分消化率的影响

Effects of Phytase on Performance and Digestibility of Nutrients in Broilers

试验选取1日龄AA肉鸡600只,随机分为6个处理,每个处理5个重复。试验基础日粮为玉米-豆粕型,1～3周龄和4～6周龄正、负对照组调整有效磷水平分别为0.43%、0.23%和0.34%、0.14%,负对照组基础上添加不同水平的植酸酶与负对照组一起形成0、250、500、750、1 000 U/kg 5个梯度。结果表明:日增重与植酸酶水平之间存在显著二次曲线相关(P<0.05);随着植酸酶添加水平的增加,胫骨强度有呈二次曲线增加的趋势(P<0.1)。进行3 d代谢试验,植酸酶不仅与粪中磷含量存在显著二次曲线相关(P<0.05),而且与粪中钙含量也有二次性响应的趋势(P<0.1)。从单个处理来看,在低磷日粮中添加500 U/kg植酸酶提高日增重和改善胫骨强度最为显著。综合各项指标二次曲线统计分析的结果,本试验日粮基础上添加750 U/kg植酸酶最为科学合理。

Six hundred 1-day-old Arbor Acre （AA） male chicks were randomly allocated to 6 groups with 5 replicates of 20 chicks each replicate. The feeding trial consisted of 2 periods （0-3- and 4-6-wk of age）. The corn-soybean meal basal diets contained available phosphorus of 0.43% and 0.23%, respectively were formulated as positive and negative control diets for broilers of 0 -3-wk of age, 0.34% and 0.14%, for 4-6-wk of age. Different diet phytase were supplemented to the negative control diet （including the negative control ） constitutes 5 gradients, 0, 250, 500, 750 and 1000 U/kg. Results showed significant conic equation correlation was detected between average daily gain and phytase addition diets（P 〈 0.05 ）. Tibia strength was improved quadratic with increasing phytase addition diets（P 〈 0.1 ）. Phytase addition diets was not only correlative secondarily to phosphorus excreta（P 〈 0.05 ） but also to calcium excreta（P 〈 0.1 ）. Only considering observations, Supplementation of 500 U/kg of diet phytase increased average daily gain and tibia strength significantly （P 〈 0.05）. From quadratic equation, the optimum adding level of phytase was 750 U/kg of diets.