饲粮精粗比对犊牛组织中基因GLUT1和FATP4及PepT1 mRNA表达的影响

Effects of concentrate to forage ratio on gene expression of GLUT1, FATP4 and PepT1 mRNA in different tissues of calf

为探明全价颗粒饲料精粗比与犊牛不同组织GLUT1、FATP4、PepT1 mRNA表达的关系,根据NRC(2001)营养需要,采用20型颗粒饲料机组,将质量比3∶1的苜蓿和小黑麦草混合,分别制成精粗比75∶25(Ⅰ)、70∶30(Ⅱ)、65∶35(Ⅲ)、60∶40(Ⅳ)的颗粒全价饲料,分别饲喂4组日龄相近、体重相近的中国荷斯坦断奶公犊牛(共12头,每组3头),预试期14 d,正试期56 d。结果表明:1)试验Ⅲ组犊牛肝脏、瘤胃、十二指肠、盲肠的GLUT1mRNA相对表达量显著高于试验Ⅳ组(P<0.05),而试验I组皱胃GLUT1 mRNA的相对表达量显著高于其他各组(P<0.05);2)试验Ⅲ组肝脏、盲肠和试验I组瘤胃、皱胃、十二指肠的FATP4 mRNA相对表达量均高于其他各组(P<0.05);3)试验I组瘤胃、皱胃、十二指肠和试验Ⅳ组肝脏及试验Ⅲ组盲肠的PepT1 mRNA相对表达量均高于其他各组。总体而言,不同精粗比全价颗粒饲料对不同组织GLUT1、FATP4、PepT1的表达具有一定的影响,精粗比为65∶35时更利于犊牛对葡萄糖、脂肪酸和蛋白质的吸收。

To know the relation on concentrate to forage ratio of pellet feed and gene expression of GLUT1, FATP4,Pep T1 mRNA in different tissues. 12 Holstein bull calves with the similar age and weight were chosed and divided into 4 groups with 3 calves. According to NRC（2001）, calves in each group were fed the pellet feed with the concentrate to forage with ratio of 75∶25（I）, 70∶30（Ⅱ）, 65∶35（Ⅲ） and 60∶40（Ⅳ） which were made from the quality ratio of alfalfa to triticale for 3∶1 by 20 type granulated feed unit. The experimental time included 14 days of preliminary trial period and 56 days of the experimental period. The results showed that 1） The expression of GLUT1 mRNA in liver, rumen, duodenum and cecum in group Ⅲ were significantly higher than that of group Ⅳ（P〈0.05）.The expression of GLUT1 mRNA in abomasum of group I were significantly higher than that of other groups（P〈0.05）. 2） The expression of FATP4 mRNA in liver, cecum of group Ⅲ and rumen, duodenum, abomasum of group I were higher than that of other groups. 3） The expression of PepT1 mRNA in rumen, duodenum, abomasum of group I, liver of group Ⅳ and cecum of group Ⅲ were higher than that of other groups. In conclusion, the different concentrate to forage ratio in pellet feed could influence the expression of GLUT1, FATP4 and Pep T1 in different tissues. The concentrate to forage ratio with 65∶35 was beneficial for calves to absorb the glucose, fat acid and protein.