转sck基因大米对小型猪肠道菌群和3种消化酶的影响

Effect of Rice Genetically Modified with CpTI to Intestinal Microflora and Digestive Enzymes of Minipigs

用表达修饰后的CpTI(豇豆胰蛋白酶抑制剂)基因大米(sck)喂养小型猪,研究其与亲本大米相比对小型猪消化功能的影响,从而评价转sck基因大米与亲本大米的实质等同性。选择断乳期雄性中国实验用小型猪15只,初始体重(6.22±0.42)kg。按窝别体重分成3组,分别为正常对照组(NG),仅喂饲市售猪饲料;亲本大米对照组(CG),喂饲70%亲本大米+基础饲料;转基因大米组(GG),喂饲70%转sck基因大米+基础饲料。基础饲料包括12%小麦麸,8%豆粕,6%酪蛋白和4%的矿物质和维生素混合物。喂养62天,测定粪便菌群及胰腺和粪便中胰蛋白酶、糜蛋白酶和淀粉酶的活性。对胃、小肠、结肠、胰腺称重并做常规组织学和病理学检查。结果表明:与亲本大米组动物相比,转基因大米组动物肠道菌群、胰腺和粪便中胰蛋白酶、糜蛋白酶和淀粉酶活性,胃肠道组织和胰腺组织均未见明显差异(P>0.05),也未见到明显非期望效应。含有CpTI的转sck基因大米未对大米在哺乳动物体内的消化过程产生明显不良影响,为进一步证明转sck基因大米与亲本大米的实质等同性提供了新的证据。

To evaluate the substantial equivalence between genetically modified rice with sck gene and the parent rice, 15 weaning male pigs weighed （6.22 ± 0.42 ） kg were divided into three groups ： （ 1 ） Normal group （NG） , fed only a commercial pig diet; （2） Control or parental rice group（CG） , fed 70% parental rice ＋ 30% basic diet; （3）GM rice group（GG） , fed 70% GM rice ＋ 30% basic diet. The basic diet included 12% wheat bran, 8% bean, 6% casein, and 4% mixture of vitamins and mineral elements. After feeding period of 62 days, the levels of trypsin, chymotrypsin and amylase in feces and pancreas and the fecal microflora were determined, and histological examination of gastrointestinal organs and pancreas were conducted. The results show： The microflora in fecal, the levels of trypsin, chymotrypsin and amylase measured in the pancreas and feces are similar in both groups fed transgenie rice and fed parental rice （P 〉 0.05 ）. There are no gastrointestinal and pancreas pathologic findings observed at necropsy in all minipigs and no marked difference in gastrointestinal organ and pancreas weights between minipigs fed non - transgenic or transgenic rice. （ P 〉 0.05 ）. It could be concluded that CpTI of this genetically modified rice with sck gene has no imperial effects on the ingestion functions in mammals. It provides another evidence for the substan- tial equivalence between genetically modified rice with sek gene and the parent rice.