基于多元统计分析的产后异食沙土奶牛生化指标的研究

Study on Biochemical Indexes of Postpartum Dairy Cows Eating Sand Based on Multivariate Statistical Analysis

本研究旨在通过产后异食沙土奶牛生化指标的变化规律,阐明产后奶牛异食沙土的可能发生机制。采用全自动血液生化分析仪分别检测了16头产后健康奶牛和15头产后异食沙土奶牛的血液生化指标,结合主成分分析(PCA)和正交偏最小二乘法-判别分析(OPLS-DA)对2组血样生化指标进行模式识别;根据OPLS-DA模型中的VIP值(VIP>1)和单因素方差分析(ANOVA)检验的P值(P<0.05)筛选2组血样差异生化标志物。结果表明:(1)产后异食沙土奶牛与健康奶牛血样生化指标轮廓存在明显差异;(2)8个差异生化标志物钙(Ca)、磷(P)、葡萄糖(Glu)、总胆固醇(TC)、甘油三酯(TG)、总蛋白(TP)、白蛋白(ALB)、球蛋白(GLB)对2组血样都具有显著的区分能力。综上表明,由于产后奶牛采食量下降,导致能量负平衡、钙磷和蛋白质摄入不足可能是引发产后奶牛异食沙土的主要原因。

This study aims to study the changes in postpartum biochemical indicators of dairy cows eating sand,and explain the possible mechanism of the heterogeneous sandy soil in postpartum dairy cows.Blood biochemical indicators of 16 postpartum healthy dairy cows and 15 postpartum Pica sand cows were detected by automatic blood biochemistry analyzer,pattern recognition of two groups of blood biochemical indicators by principal component analysis(PCA)and orthogonal partial least squares-discrimination analysis(OPLS-DA).Differential biochemical markers of blood samples between the two groups were screened according to the VIP values in the OPLS-DA model(VIP>1)and the one-way analysis of variance(ANOVA)P values(P<0.05).The results showed that there was significant difference in the profile of blood biochemical indicators between postpartum Pica sand and health cows.Eight differential biochemical markers calcium(Ca),phosphorus(P),total protein(TP),albumin(ALB),globulin(GLB),glucose(Glu),total cholesterol(TC),triglycerides(TG)had significant discriminating power between the two groups of blood samples.In summary,due to the decreased feed intake in postpartum cows,negative energy balance,and insufficient intake of calcium,phosphorus and protein may be the main cause of postpartum dairy cows eating sand.