排空强饲法测定鸡饲粮表观代谢能值的灵敏度与置信限

Sensitivity and Confidence Limit of Empting-Force Feeding Method for Determining Apparent Metabolizable Energy of Diets in Rooster

本研究旨在通过探讨排空强饲法测定鸡饲粮表观代谢能(AME)值的灵敏度及样品间显著差异的置信限,为国家标准方法 GB/T 26437—2010的应用提供参考。试验1采用2×5两因素完全随机设计,即2个基础饲粮和5个稀释剂水平(2%、4%、6%、8%和10%),检验排空强饲法测定的AME值对计算值的线性反应量。试验2通过分析上述10个饲粮样品、4次空白样品测试中AME值的方差,计算2个样品间AME值差异显著时所对应的置信限。结果表明:在2个基础饲粮条件下,稀释剂的水平与稀释后饲粮的AME值呈显著的线性关系(P<0.01),而二次函数关系与线性失拟检验均不显著(P>0.05)。以饲粮AME计算值为依变量,以排空强饲法AME实测值为应变量,作线性回归分析,得出斜率为0.987(P<0.01),这表明排空强饲法的灵敏度很高。排空强饲法测定4次空白样品及10个饲粮样品的AME值方差无显著差异(P>0.05)。根据排空强饲法测定饲粮AME值标准差的平均值,计算出2个饲粮样品间AME值显著性差异的置信限为0.27 MJ/kg DM。综上所述,排空强饲法测定饲粮的AME值具有满意的灵敏度。0.27 MJ/kg DM的置信限将为检测饲粮样品间AME值是否有显著差异提供参考。

The sensitivity and confidence limit of empting-force feeding method for determining the apparent metabolizable energy （AME） values of diets in rooster were investigated to make a reference for the national standard method of GB/T 26437—2010. In experiment 1, a 2×5 completely randomized design with 2 basal diets and 5 diluent levels （2%, 4%, 6%, 8% and 10% of peanut hull in the basal diets） was adopted to determine the response of determined AME values using empting-force feeding method to the calculated AME values. In experiment 2, according to the variances of the AME values of 10 diets in experiment 1 and 4 batches of blank samples, the confidence limit was determined for empting-force feeding method to differentiate the AME values between two samples. The results showed that in two groups of experimental diets composed of the basal diet and peanut hull, there was a significant linear effect of peanut hull content on the AME values of the diets （P〈0.01）, whereas the quadratic effects and lack-of-fit of linearity were not significant （P〉0.05）. A linear regression with a slope of 0.987 was observed between the independent variable of calculated AME values and dependent variable of measured AME values of the diets （P〈0.01）, indicating there was a high sensitivity of empting-force feeding method. There was no significant difference in the variances of the AME values of the 10 diets and the blank sample （P〉0.05）. According to the mean of standard deviation of dietary AME values, 0.27 MJ/kg DM of confidence limit was calculated for empting-force feeding method to differentiate the AME values between two samples. In conclusion, the sensitivity of empting force-feeding is satisfactory. The 0.27 MJ/kg DM of confidence limits is a critical parameter for the determination of significant difference among diets.