本试验旨在研究乳酸锌对“杜洛克×长白×约克冶( DLY)仔猪生长性能、小肠形态学、小肠黏膜金属硫蛋白1(MT1)和组织急性期蛋白(APP) mRNA表达的影响,探索乳酸锌对仔猪免疫调节的机制。选用24头(公母各占1/2)35日龄DLY仔猪为研究对象,试验猪随机分为对照组和试验组,每组12个重复,每个重复1头猪。对照组饲喂基础饲粮,试验组饲喂在基础饲粮中添加乳酸锌,使锌添加量达到100 mg/kg的试验饲粮。试验期25 d。结果表明,添加乳酸锌显著提高仔猪生长性能(P<0.05),极显著增加小肠绒毛长度和降低隐窝深度(P<0.01)。添加乳酸锌显著诱导仔猪十二指肠、空肠、回肠黏膜MT1 mRNA和肝脏、胰脏、脾脏、肾脏、十二指肠、空肠、回肠组织APP mRNA表达上调( P<0.05),小肠MT1 mRNA表达谱为:空肠>十二指肠>回肠;被检测的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以胰腺、肾脏和肝脏表达量最高,而脾脏和十二指肠则微量表达。结果提示,添加乳酸锌可极显著增加仔猪小肠绒毛长度,降低隐窝深度,改善养分消化利用;通过提高十二指肠、空肠和回肠黏膜 MT1 mRNA 表达量,诱导机体组织 CRP、HP、AGP 和 SAA mRNA表达上调的方式,增加仔猪的抗病能力,从而改善仔猪的生长性能。
This study was conducted to investigate the effects of zinc lactate on growth performance, intestinal morphology, metallothioneins 1(MT1) in intestinal mucosa and acute phase proteins (APP) mRNA expres-sion in tissues. of‘durocílandraceíyork' ( DLY) weaner piglets Twenty-four ( half male and half female) 35-day-old DLY weaner piglets in this study were randomly divided into control group and experimental group with 12 replicates per group and 1 piglet per replicate. Control group was fed a basal diet, while the experi-mental group was fed an experimental diet which was the basal diet added with zinc lactate ( zinc added level at 100 mg/kg) . The experiment lasted for 25 days. The results showed that, adding zinc lactate significantly im-proved the growth performance of weaner piglet ( P<0 . 05 ) , significantly increased villi length and decreased crypt depth of piglets ( P<0 . 01 ) , and significantly induced the upregulation of MT1 mRNA expression in du-odenum, jejunum and ileum mucosa and APP mRNA expression in liver, pancreas, spleen, kidney, duode-num, jejunum and ileum of piglets (P <0. 05). MT1 mRNA expression profile in small intestine was jeju-num, duodenum and ileum, respectively; mRNA expressions of C-reactive protein ( CRP ) , haptoglobin ( HP) , α1-acid glycoprotein ( AGP) and serum amyloid-A ( SAA) were detected the highest in the pancreas, kidney and liver, but trace expression in spleen and duodenum. It is suggested that zinc lactate significantly in-crease small intestinal villi length, decrease crypt depth, and zinc lactate may improve nutrient utilization, in-ducing the upregulation of CRP, HP, AGP and SAA mRNA expression in tissues by increasing MT1 mRNA expression in duodenum, jejunum and ileum, and increase disease resistance of piglets, thereby growth per-formance can be improved for weaner piglets.