烟酸和烟酸铬对断奶犊牛应激的影响

选用三月龄断奶荷斯坦犊牛30头,将其等分为三组,对照组为基础日粮,烟酸组和烟酸铬组分别在基础日粮中添加400 mg/kg的烟酸和6.4 mg/kg的烟酸铬.结果表明:烟酸和烟酸铬在前10 d对犊牛的增重影响不明显(P>0.05);20～30 d,烟酸组和烟酸铬组的平均日增重比对照组分别提高5%和27.6%;30～40 d,烟酸组和烟酸铬组的平均日增重比对照组分别提高12.8%和18.11%;而最后一个阶段,烟酸组和烟酸铬组的平均日增重比对照组分别提高8.9%和7.45%.试验期间,烟酸铬组与对照组相比提高T3、T4、生长激素、胰高血糖素水平分别为25.68%(P<0.05)、17.31%、6.73%、9.03%;烟酸组与对照组相比提高T3、T4水平分别为11.5%、12.7%.

Effects of Niacin and Chromium-nicotinate on Weaning-stressed Calves

Thirty Holstein weaning calves at 30 weaning days similar in weight were divided into the control, niacin, chromium nicotinate groups.Effects of niacin and chromium nicotinate on performances of the weaning-stressed calves were studied.The results showed that feeding niacin and chromium nicotinate improved the daily gain of weaning calves in the testing period.But there was no effect on the weight improvement in the testing period which was from beginning to the tenth days;in the testing period of 20th ～30th days, the average daily gain respectively raised by 5%, 27.6% by feeding niacin and chromium nicotinate compared with the control;in the testing period of 30th ～40th days, the average daily gain respectively raised by 12.8%, 18.11% by feeding niacin and chromium nicotinate compared with the control; The last testing phase,the average daily gain respectively raised by 8.9%, 7.45% by feeding niacin and chromium nicotinate as compared with the control; The levels of T3, T4, GH, GLU of serum respectively raised by compared with the control; The levels of T3, T4 of serum respectively raised by 11.5%、12.7% by niacin administration, compared with the control.