饲料中添加钴、维生素B12对犊牛生长的影响

选用同一头黑白花种公牛与初产秦川母牛杂交产下的28头犊牛（产期接近）为试验牛，随机分为4组（试验1、试验2、试验3、试验4），每组7头。试验1饲喂本场加工的犊牛精饲料，试验2、3、4组，在饲喂本场加工的犊牛精饲料基础上，另在每千克饲料中分别添加VB12 0．48mg、钴0.48g、钴和VB12各0.48g。试验结果表明：日增重，试验1与试验4相比差异极显著（P〈0．01），试验1分别与试验2、试验3相比差异显著（P〈0．05），试验4组分别与试验2、试验3组相比差异显著（P〈0．05）；试验2与试验3相比差异不显著（P〉0．05）。

Effect of adding Cobalt and VB12 on the growth of calf

The study was conducted with 28calf which were descendant of Blackand W hite bull cross m ating Qinchuan cow. 28calf were divided into four groups,which were fed base diet(trial1),adding 0.48m g VB12 in base diet(trial2),adding 0.48m g VB12Cobalt in base diet (trial3), adding 0.48m g Cobalt and 0.48m gVB12 inbase diet(trial4)respectively.The results showed that average daily gain of the fourthgroup was significantly higher than that of feeding base diet (P<0.01); the averagedaily gain of feeding base diet was lower than that of the second and third groupsrespectively(P<0.05);the average daily gain of fourth group was higher than that ofthe second and third groups respectively (P<0.05); the average daily gain had nodifference between the second group and third group(P>0.05).