日粮不同氮硫比和铜水平对肉牛血液指标的影响

肉牛饲喂不同氮硫比水平日粮,对铜的需要量也不相同。为确定不同氮硫比水平下,铜的适宜需要量,本试验选用3头体况良好、体重相近(450±50)kg,安装有永久性瘤胃瘘管、十二指肠近端瘘管和回肠末端瘘管的利木赞×鲁西黄牛杂交一代阉牛作为试验动物,采用3×3拉丁方设计,测定不同氮硫比和铜水平对肉牛血液指标的影响。结果表明:日粮氮硫比为10.73和7.24时,血清铜蓝蛋白(CP)和超氧化物歧化酶(SOD)的活性,不同铜水平间差异并不显著(P>0.05);日粮氮硫比为5.47时,10 mg/kg铜水平组,血清SOD和CP活力显著低于25mg/kg和50mg/kg铜水平组(P<0.05),25 mg/kg和50 mg/kg铜水平组间差异不显著(P>0.05)。

Effects of Different Ratio of Nitrogen to Sulphate and Copper on Blood Parameters in Beef

Beef cattles have different copper requirements when they are fed diets with different nitrogen/sulfur levels.Three beef calltles of similar body weight with permanent rumen fistulae were used in this experiment to study the effect of different dietary levels of nitrogen/sulfur and copper on blood index,and design of 3×3 latin square was used.The results showed that the activities of serum CP and SOD were not significantly affected by different copper levels in nitrogen/sulfur levels of 10.73 and 7.24;In nitrogen/sulfur levels of 5.47,the activities of serum CP and SOD in 10 mg/kg copper levels were lower notably than 25 mg/kg and 50 mg/kg copper levels,and the activities of serum CP and SOD in 25 mg/kg and 50 mg/kg had no significant differences.