补饲非蛋白氮补充料对放牧牛群生产性能的影响

Study on the Grazing Cattle Feeding with Non-protein Nitrogen Supplementation

本试验旨在研究补饲非蛋白氮(NPN)补充料对放牧牛群生产性能的影响。试验在春末夏初放牧前,选择30头9～10月龄、体重150～170kg的中国西门塔尔太行类群小公牛,分为对照组、试验1组和试验2组,进行放牧加补饲试验。试验1组日补饲玉米粉1.0kg;试验2组在试验1组的基础上增补NPN补充料0.25kg。进行了为期100d的放牧补饲效果试验。结果表明,对照组、试验1组、试验2组日增重分别为0.622、0.839和1.051kg。试验1组比对照组日增重提高217g;试验2组比对照组和试验1组日增重分别提高429和212g。3组间增重差异显著。因此,北方山坡草地放牧牛群补饲少量精料效果明显,同时,补喂少量NPN补充料经济效益更为显著。

The experiment was conducted to investigate the effect of non-protein nitrogen supplementation on the grazing cattle.Thirty Chinese Simmental bull Taihang（weighted 150to 170kg）were chosen and divided into 3groups,which were control group,experiment group 1and experiment group 2.One kilogram corn flour was supplemented in experiment group 1 and 0.25kg NPN supplementation was added at the basis of experiment group 1in experiment group 2.The experiment was conducted at the time before grazing,which is the late spring and early summer,and lased 100days.Results showed that the average daily gain was 0.622,0.839and 1.051kg for the control group,experiment group 1and experiment group 2,respec-tively.Average daily gain was increased 217g for the experiment group 1than the control group and increased 429and 212g for experiment group 2than control group and experiment group 1,respectively.The difference among three groups was re-markable significant,and weight gain differed significantly between experiment group 2and control group.It was concluded that small amount of concentrate supplementation has obvious effect on the grazing cattle in northern slopes and small amount of NPN supplementation would have more significant economic benefits.