干奶期奶牛不同能量摄入对其肝脏胰岛素受体mRNA表达的影响

将健康围产期奶牛30头随机分为3组,预产前28 d分别饲喂奶牛标准日粮（能量摄入100%组）、标准日粮增加20%日粮（能量摄入120%组）和标准日粮减少20%日粮（能量摄入80%组）,产后各组奶牛均饲喂标准的产奶日粮,至产后56d结束,采用半定量RT-PCR方法,观测干奶期不同能量摄入水平对围产期健康奶牛肝脏胰岛素受体（IR）基因表达的影响.试验结果表明,干奶期低能饲喂奶牛,产后肝脏IR mRNA表达增加,提示低能饲喂有利于调节奶牛产后血糖平衡.

Effect of Energy Intake Level on the Expression of IR mRNA in the Liver of Periparturient Cows

The objective of present study was to investigate the effect of energy intake during the dry period on the expression of IR mRNA in the liver of periparturient diary cows.Thirty healthy multiparous Holstein cows were randomly allocated into three groups and fed 100% energy diet(standard diets),120% energy diet and 80% energy diet,respectively,beginning at the 28th day before parturition.After calving,all the cows were offered the lactation ration ad libitum until the 56th day postpartum.The results indicated that the cows fed with low energy diet during the dry period had the significant highest level of IR mRNA in the liver than that in the cows fed with 120% energy diet and 100% energy diet.It is concluded that the low energy diet during the dry period could be helpful to regulation of blood glucose balance in the periparturient diary cows by enhancing insulin receptor quantity.