罗伊氏乳杆菌LR1对断奶仔猪血清生化指标和肠道营养物质转运载体mRNA表达的影响

Effects of Lactobacillus reuteri LR1 on Serum Biochemical Indexes and mRNA Expressions of Intestinal Nutrient Transporters of Weaned Piglets

本试验旨在研究罗伊氏乳杆菌LR1对断奶仔猪血清生化指标和肠道营养物质转运载体mRNA表达的影响。选取144头初始体重为(6.49±0.01) kg的21日龄杜×长×大断奶仔猪,随机分为3组,每组8个重复,每个重复6头。对照组饲喂基础饲粮,抗生素组饲喂基础饲粮+100 mg/kg喹乙醇+75 mg/kg金霉素,罗伊氏乳杆菌组饲喂基础饲粮+5×1010CFU/kg罗伊氏乳杆菌LR1。试验期为14 d。结果显示:1)与对照组相比,饲粮添加抗生素显著提高了血清葡萄糖(GLU)的含量(P<0.05),且显著降低了血清尿素氮(UN)的含量(P<0.05)。2)与对照组相比,饲粮添加罗伊氏乳杆菌LR1显著提高了十二指肠胃动素(MLN)和空肠胆囊收缩素(CCK)的mRNA表达量(P<0.05);饲粮添加抗生素显著提高了十二指肠MLN的mRNA表达量(P<0.05)。3)与对照组相比,饲粮添加罗伊氏乳杆菌LR1显著提高了十二指肠Na+依赖性谷氨酰胺载体2(ASCT2)、阳离子氨基酸运载体1(CAT1)、小肽转运体1(PepT1)和空肠中性和碱性氨基酸转运载体(rBAT)以及空肠与回肠y+L氨基酸转运体1 (y+LAT1)的mRNA表达量(P <0.05);饲粮添加抗生素显著提高了空肠y+LAT1、CAT1、PepT1和空肠与回肠哺乳动物雷帕霉素靶蛋白(mTOR)的mRNA表达量(P<0.05)。4)与对照组相比,饲粮添加罗伊氏乳杆菌LR1显著提高了十二指肠小肠脂肪酸结合蛋白(I-FABP)、乙酰辅酶A羧化酶α(ACCα)、脂肪酸合成酶(FASN)和十二指肠与空肠脂肪酸结合蛋白3(FABP3)以及十二指肠、空肠与回肠过氧化物体增殖物激活受体γ(PPARγ)的mRNA表达量(P<0.05);饲粮添加抗生素显著提高了空肠ACCα的mRNA表达量(P<0.05)。5)与对照组相比,饲粮添加罗伊氏乳杆菌LR1显著提高了空肠和回肠钠-葡萄糖协同转运蛋白1(SGLT1)的mRNA表达量(P<0.05);饲粮添加抗生素显著提高了十二指肠SGLT1、钠-葡萄糖协同转运蛋白3(SGLT3)的mRNA表达量(P<0.05)。综上所述,饲粮中添加5×1010CFU/kg罗伊氏乳杆菌LR1对断奶仔猪的肠道营养物质转运具有良好的促进作用,表现为促进断奶仔猪肠道物理消化和化学消化,促进小肽、氨基酸及脂肪酸吸收转运,增强脂肪酸的合成。罗伊氏乳杆菌LR1在替代猪饲用抗生素方面具有巨大潜力,可用于开发新型猪饲料抗生素替代物。

This experiment was conducted to investigate the effects of Lactobacillus reuteri（L.reuteri） LR1 on serum biochemical indexes and mRNA expressions of intestinal nutrient transporters of weaned piglets.A total of 144 weaned piglets（Duroc×Landrace×Yorkshire,21 days of age） with an initial body weight of（6.49±0.01） kg were randomly allocated to 3 groups consisting of 8 replicates with 6 piglets each replicate.Piglets in control group were fed a basal diet,those in antibiotics group were fed the basal diet＋100 mg/kg olaquindox ＋75 mg/kg aureomycin,and those in L.reuteri group were fed the basal diet＋5×10^10 CFU/kg L.reuteri LR1.The experiment lasted for 14 days.The results showed as follow s：1） compared with the control group,antibiotics supplementation significantly increased serum glucose（GLU） content（P〈0.05）,and significantly decreased urea nitrogen（UN） content（P〈0.05）.2） Compared with the control group,L.reuteri LR1 supplementation significantly increased the mRNA expressions of motilin（MLN） in duodenum and cholecystokinin（CCK） in jejunum（P〈0.05）;antibiotics supplementation significantly increased the mRNA expression of MLN in duodenum（P〈0.05）.3） Compared with the control group,L.reuteri LR1 supplementation significantly increased the mRNA expressions of Na^＋dependent glutamine transporter 2（ASCT2）,cationic amino acid transporter 1（CAT1）,peptide transporter 1（PepT1） in duodenum,neutral and basic amino acid transport protein（rBAT）,y^＋L amino acid transporter 1（y^＋LAT1） in jejunum and y^＋LAT1 in ileum（P〈0.05）;antibiotics supplementation significantly increased the mRNA expressions of y^＋LAT1,CAT1,PepT1 in jejunum and mammalian target of rapamycin（mTOR） in jejunum and ileum（P〈0.05）.4） Compared with the control group,L.reuteri LR1 supplementation significantly increased the mRNA expressions of intestinal fatty acid binding protein（I-FABP）,fatty acid binding protein 3（FABP3）,acetyl CoA carboxylase α（ACCα）,fatty acid synthase（FASN） in duodenum and FABP3 in jejunum and peroxisome proliferator-activated receptor γ（PPARγ） in duodenum,jejunum and ileum（P〈0.05）;antibiotics supplementation significantly increased the mRNA expression of ACCα in jejunum（P〈0.05）.5） Compared with control group,L.reuteri LR1 supplementation significantly increased the mRNA expression of sodium-dependent glucose transporter 1（SG LT1） in jejunum and ileum（P〈0.05）;antibiotics supplementation significantly increased the mRNA expressions of SG LT1 and sodium-dependent glucose transporter 3（SG LT3） in duodenum（P〈0.05）.In conclusion,diet supplemented with 5×10^10 CFU/kg L.reuteri LR1 has favorable promoting effects on transportation of intestinal nutrients in weaned piglets,characterized by promoting physical and chemical digestion,facilitating absorption and transportation of peptides,amino acids and fatty acid,enhancing protein and fatty acid synthesis in intestine of weaned piglets.Hence,L.reuteri LR1 has great potential for the replacement of in-feed antibiotics and can be used for development of antibiotics substitution of pig feeds.