【摘要】 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。更多还原

【Abstract】 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.更多还原