多重线性回归法测定猪内源磷排泄量及饲料磷真消化率的研究

本研究旨在采用多重线性回归法测定生长猪内源磷排泄量及高粱和豆粕中磷的真消化率。试验选用6头健康大白×长白阉公猪为消化试验动物,平均体重为(23.6±1.23)kg。采用6×6拉丁方设计,设6个磷水平(0.08%、0.15%、0.23%、0.30%、0.38%、0.53%),以豆粕、葡萄糖、玉米淀粉等为基础,以高粱和豆粕为磷唯一来源,配制半纯合试验饲粮。饲粮中添加0.35%Cr2O3作为外源指示剂。试验分6个试验期,每期8d,其中6d适应期,2d收粪期。饲粮中磷表观消化率受饲粮中磷水平的影响(P<0.05),并随饲粮中磷水平的提高由14.88%增大至34.88%。在以g/kgDMI为计量单位条件下,生长猪粪磷的排出量与饲粮磷的摄入量呈线性关系(P=0.0001)。结果表明,多重线性回归法可用于生长猪内源磷排泄量和植物性饲料磷真消化率的测定;以豆粕-高粱型模型饲粮测定出生长猪内源磷排泄量为0.2940g/kgDMI,高粱中磷的真消化率为56.05%,豆粕中磷的真消化率为39.41%。

Study on Endognenous Outputs and True Digestibility of Phosphorus with Sorghum and Soybean Meal in Growing Pigs by Multiple Linear Regression Analysis Technique

In the study,regression analysis technique was used to measure the fecal phosphorus (P) endogenous outputs and true P digestibility values with sorghum and soybean meal in growing pigs. Six healthy Yorkshire × Landrace barrows, with average initial body weight of (23.6 ± 1.23) kg,were fed six diets according to a 6 × 6 Latin square design. The diets were soybean meal-corn starch-glucose type with six dietary levels of P (0.08%, 0.15%, 0.23 %, 0.30 %, 0.38 %, 0. 53%) from sorghum and soybean meal. Diet P was only provided by sorghum and soybean meal. Chromic oxide (3.5 g/kg of diet,as-fed basis) was included in the diets as digestibility marker. Each experimental period consisted of 8 days with 6-day adaptation and 2-day collection of representative fecal samples. The results showed that the apparent fecal P digestibility values in diets were affected (P＜0.05) by P levels in the assay diets. Linear relationship (P = 0.000 1) ,expressed as g/kg DM diet intake,was existed between fecal outputs and dietary inputs of P. In conclusion, the results suggested that the endogenous P outputs can be determined by multiple linear regression analysis technique. The P endogenous outputs for pig were 0. 294 0 g/kg DMI,true digestibility value of P in sorghum was 56.05% ,and true digestibility value of P in soybean was 39.41%.