本试验旨在比较饲粮纤维水平对杜洛克仔猪、高黎贡山仔猪生产性能、小肠形态学、小肠黏膜金属硫蛋白1( MT1)和组织急性期蛋白( APPs)基因表达的影响。选用35日龄高黎贡山断奶仔猪和杜洛克断奶仔猪各24头(公母各占1/2)为研究对象,试验设对照组和试验组(每组12个重复,每个重复1头猪),分别饲喂纤维水平为3.53%和7.04%饲粮,饲养至60日龄结束。考察仔猪生产性能,观察小肠形态学变化,检测十二指肠、空肠、回肠黏膜MT1 mRNA相对表达量以及肝脏、胰脏、脾脏、肾脏、十二指肠、空肠、回肠7种组织中4种APPs[ C-反应蛋白( CRP)、触珠蛋白( HP)、α1-酸性糖蛋白( AGP)和血清淀粉样蛋白A( SAA)] mRNA相对表达量。结果表明:饲粮纤维水平为7.04%时,高黎贡山仔猪日增重、日采食量显著高于杜洛克仔猪( P<0.05),料重比显著低于杜洛克仔猪( P<0.05);高黎贡山仔猪十二指肠、空肠、回肠的绒毛长度极显著大于杜洛克仔猪(P<0.01);十二指肠、空肠隐窝深度极显著低于杜洛克仔猪(P<0.01);十二指肠、空肠、回肠绒毛长度/隐窝深度极显著大于杜洛克仔猪(P<0.01)。饲喂纤维水平为7.04%饲粮的高黎贡山仔猪十二指肠黏膜中MT1 mRNA相对表达量极显著高于饲喂纤维水平为3.53%饲粮的高黎贡山仔猪及饲喂纤维水平为7.04%或3.53%饲粮的杜洛克仔猪( P<0.01)。被测组织中均能检测出CRP、HP、AGP、SAA mRNA的表达。饲粮纤维水平为7.04%时,绝大部分组织的APPs mRNA相对表达量均为高黎贡山仔猪显著高于杜洛克仔猪( P<0.05)。上述结果表明,高黎贡山仔猪相对杜洛克仔猪更加适应高纤维水平饲粮;高黎贡山仔猪通过上调MT1及APPs mRNA的表达,增加仔猪的抗病能力,从而改善仔猪的生产性能。
This study was conducted to compare the effects of dietary fiber level on performance, intestinal mor-phology, mRNA expression of metallothioneins 1 ( MT1) in intestinal mucosa and acute phase proteins ( APPs) in tissues of Gaoligongshan and Duroc piglets. Each twenty four ( half male and half female) Duroc and Gaoli-gongshan weaner piglets of 35 days old were selected. They divided into control group and experimental group with 12 replicates per group and 1 piglet per replicate. Piglets in the control group and the experimental group were fed the diets with the fiber level was 3.53% and 7.04%, respectively. The experiment finished at 60 days old. The performance, intestinal morphological change, mRNA relative expression of MT1 in duodenum, jeju-num, ileum mucosa and four kinds of APPs [ C-reactive protein ( CRP) , haptoglobin ( HP) ,α1-acid glycopro-tein ( AGP) and serum amyloid A ( SAA) ] in liver, pancreas, spleen, kidney, duodenum, jejunum and ileum were detected. The results showed as follows:when dietary fiber level was 7.04%, daily gain and daily feed in-take of Gaoligongshan piglets was significantly higher than those of Duroc piglets ( P<0.05) , while feed conver-sion ratio was significantly lower than that of Duroc piglets ( P<0.05);villus length of duodenum, jejunum and ileum of Gaoligongshan piglets was significantly higher than that of Duroc piglets ( P<0.01);crypt depth of duo-denum and jejunum was significantly lower than that of Duroc piglets ( P<0.01);villus length/crypt depth of du-odenum, jejunum and ileum was significantly higher than that of Duroc piglets (P<0.01). When dietary fiber level was 7. 04%, MT1 mRNA relative expression in duodenum mucosa of Gaoligongshan piglets fed the diet with 7.04% fiber level was significantly higher than that of Gaoligongshan piglets fed the diet with 3.53% fiber level and Duroc piglets fed the diets with 7.04% or 3.53% fiber level ( P<0.01) . CRP, HP, AGP and SAA mR-NA expression could be detected in the measured tissues. When dietary fiber level was 7.04%, APPs mRNA rela-tive expression in most tissues of Gaoligongshan piglets was significantly higher than that of Duroc piglets. These results suggest that Gaoligongshan piglets is better adapted to high fiber level diets than Duroc piglets;disease re-sistance is improved of Gaoligongshan piglets by increasing MT1 and APPs mRNA expression, thereby impro-ving the performance of piglets.