不同粗蛋白水平日粮对荷斯坦牛生长性能和血液生化指标的影响

摘要

The purpose of this test is to study the effect of dietary crude protein on growth performance and blood biochemical parameters of 140 ～ 200kg Holstein cows.21 healthy Holstein cows (body weight,142.58 ± 1.50kg) were randomly divided into three groups with 7 duplicates per group.Dietary energy level of three diets was 12.82 MJ / kg DM.Crude protein levels were separately 16.10％,15.10％ or 14.11％ of DM.The results showed as follows:Dietary crude protein has significantly effect on body weight growth.The body weight growth was highest for the cows fed middle crude protein diet,significant higher than that fed high crude protein diet (P＜0.05),but had no significant difference with cows fed the low crude protein diet(P＞0.05).The total weight gain in the highprotein group,and low-protein group were lower 10.21％,5.21％ than that of the middle group.The trend of the body measurement indicators is similar to the weight growth.Dietary crude protein levels had no significant effects on the serum total cholesterol,blood urea nitrogen,and β-hydroxybutyrate levels (P＞0.05) had significant effects on the contents of glucose,non-esterified fatty acids (NEFA) in serum (P＜0.05).In the present experimental conditions,the diet with DE at 12.82 MJ / kg DM and crude protein at 15.10％ DM could meet the nutrient requirement of 140～ 200kg Holstein cows.%本试验选用21头月龄、体重相近的健康荷斯坦母牛,随机分为3组,每组7头.3个试验组日粮能量水平一致(12.82MJ/kg,DM),粗蛋白水平分别为16.10％、15.10％、14.11％(DM基础).结果表明,日粮粗蛋白水平对犊牛增重影响显著,中蛋白组试验牛体增重最多,与高蛋白组相比差异极显著(P＜0.01),低蛋白组与其他两组差异不显著(P＞0.05).中蛋白组试验牛平均日增重比高蛋白组、低蛋白组分别高出10.22％、5.22％.各体尺指标变化趋势与体重变化趋势相似.日粮粗蛋白水平对血清总胆固醇、尿素氮和β-羟丁酸的影响不显著(P＞0.05)；但对葡萄糖、非酯化脂肪酸(NEFA)的影响显著(P＜0.05).在本试验条件下,消化能12.82MJ/kg(DM)、粗蛋白15.10％ (DM)的日粮能够满足140～200kg荷斯坦母牛的营养需要.