【摘要】 本研究旨在探讨日粮中不同钼铜水平对肉牛血液生化指标的影响。选用性别一致、年龄、体重相近(340±10)kg的3头健康未去势公牛作为试验动物。试验采用3×3拉丁方设计,分2期进行,第一期日粮钼的水平为0.27 mg/kg DM,第二期钼的水平为5.27 mg/kg DM。每期日粮铜的添加量分别为:10 mg/kg(低铜组),25 mg/kg(中铜组),50 mg/kg(高铜组)3个水平。颈静脉采血测定血铜、血清铜蓝蛋白(ceruloplasmin,Cp)和血浆中过氧化物歧化酶(superoxide dismutase,SOD)的活性。试验结果表明:在同一钼水平下,随铜水平的增加,牛体内血铜含量、血浆中SOD活性和血清Cp的活性逐渐增加。其中钼水平为0.27 mg/kg时,这种变化不显著(P>0.05)。钼水平为5.27 mg/kg时,添加10 mg/kg铜,血铜含量和血浆中SOD活性显著小于其他2个铜水平(P<0.05),Cp活性小于其他2个铜水平,且差异极显著(P<0.01)。在同一铜水平下,低钼组2种酶的活性普遍高于高钼组。日粮钼水平为0.27 mg/kg时,添加10 mg/kg铜可满足机体需要;日粮钼水平为5.27 mg/kg时,添加25 mg/kg铜较适宜:牛在缺铜时,与血浆SOD的活性比较,血清Cp更宜作为评价铜营养缺乏的指标;铜满足机体需要后,血铜、血清Cp和血浆SOD均对铜和钼的变化不敏感。血铜和血清铜蓝蛋白与日粮铜水平呈强相关。更多还原

【Abstract】 This study was conducted to investigate effects of different dietary levels of copper and molybdenum on the blood biochemical index in beef cattle.In this experiment,3×3 Latin-square design was used,and three unsaturated bulls with similar age and weight were divided into three treatments.The experiment included two periods:in the first one,the dietary Mo level was 0.27 mg/kg DM,and 5.27 mg/kg DM in the second one.There were 10 mg/kg,25 mg/kg and 50 mg/kg copper added to the diet in each period.The blood samples taken from neck vein were used to test the blood copper concentration and the activity of ceruloplasmin(Cp) and superoxide dismutase(SOD).The result as follows:the blood copper concentration,the activity of CP and SOD increased with the rise of copper in diet.The difference was not evident on the low dietary Mo level(P>0.05),but on the high dietary Mo level,the difference of the blood copper concentration and the activity of SOD were less than the others significantly(P<0.05),and the activity of Cp was less than the others significantly(P<0.01) when 10 mg/kg copper was added.On identical dietary copper level,the activities of the two enzymes in low Mo group is higher than those in the high one.When the dietary Mo level was 0.27 mg/kg DM,the diet containing 10 mg/kg Cu could meet the requirement of beef cattle.While the dietary Mo concentration was 5.27 mg/kg,adding 25 mg/kg Cu could be better.When the cattle were in lacking of Cu,compared to activity of plasma SOD,serum Cp should be a good index for evaluating Cu nutritional status. When Cu meets cattle’s requirement,the blood copper concentration and activities of serum Cp and plasma SOD were not sensitive to the change of dietary Cu and Mo levels.更多还原