纳米氧化锌对断奶仔猪生长、腹泻、肠道微生物和通透性的影响

选用108头平均体重为7.2 kg杜×长×大断奶仔猪,随机分成3组,对照组饲喂基础饲粮;氧化锌组在基础饲粮中添加2 000 mg/kg锌(氧化锌);纳米氧化锌组在基础饲粮中添加500 mg/kg锌(纳米氧化锌),试验期14 d。结果表明:与对照组相比,添加500 mg/kg纳米氧化锌和2 000 mg/kg氧化锌分别提高日增重16.20%(P<0.05)和14.94%(P<0.05),提高日采食12.63%(P<0.05)和13.66%(P<0.05),显著降低断奶后7 d和14 d腹泻指数(P<0.05),显著降低血浆D-乳酸和二胺氧化酶活性(P<0.05)。添加500 mg/kg纳米氧化锌显著降低小肠和结肠内容物中梭菌和大肠杆菌数量;添加2 000 mg/kg氧化锌显著降低结肠内容物中梭菌数量。结果提示,断奶仔猪饲粮中添加500 mg/kg锌(纳米氧化锌)可提高仔猪生长性能,降低腹泻率和肠道通透性,改善肠道微生态,其效果与添加2 000 mg/kg锌(氧化锌)相当。

Effects of Nano Zinc Oxide on Performance, Diarrhea, Intestinal Microflora and Permeability of Weanling Pigs

A total of 108 weaning pigs(Duroc×Landrace×Yorkshire),with an average initial weight of 7.2 kg weaned at 27 ± 1 d age were used to investigate the effects of nano zinc oxide(nano-ZnO) on performance,diarrhea,intestinal microflora and permeability of weanling pigs.The pigs were allocated to three dietary treatments for two weeks,each of which was replicated six times with six pigs per replicate.The dietary treatments were: basal diet,basal diet + 500 mg/kg of Zn as nano-ZnO,basal diet + 2 000 mg/kg of Zn as ZnO.The results showed that as compared with the control,supplementation with nano-ZnO and ZnO improved(P<0.05) average daily gain by 16.20%(P<0.05)and 14.94%(P<0.05),improved daily feed intake by 12.63%(P<0.05)and 13.66%(P<0.05),decreased(P<0.05) fecal scores at d 7 postweaning and d 14,reduced(P<0.05) plasma D-lactate and diamine oxidase.Supplemental nano-ZnO reduced(P <0.05) number of intestinal Clostridium and Escherichia coli as compared with the control.Supplemental ZnO reduced(P<0.05) the viable counts of Clostridium in proximal colon as compared with control while had no(P>0.05) effect on intestinal Escherichia coli.The results indicated that supplementation of 500 mg/kg of Zn as nano-ZnO was as effective as 2000 mg/kg of Zn from ZnO for enhancing growth performance,alleviating diarrhea,as well as improving intestinal microflora and barrier function of weanling pigs.