载锌凹凸棒石对断奶仔猪生长性能、器官指数、生化指标及抗氧化能力的影响

Effects of zinc-bearing palygorskite on growth performance,organ index,biochemical indexes and anti-oxidative capacity in weaned piglets

将128头25日龄、平均初始体重为(8.59±0.40)kg的杜×长×大杂交断奶仔猪随机分为4组(对照组、试验Ⅰ~Ⅲ组),每组4个重复,每个重复8头,公母各半,分别饲喂基础日粮+110 mg·kg^-1抗生素(吉他霉素)+2000 mg·kg^-1 ZnO(对照组)、基础日粮+55 mg·kg^-1抗生素(吉他霉素)+1000 mg·kg^-1 ZnO+2000 mg·kg^-1载锌凹凸棒石(Zn-Pal)(试验Ⅰ组)、基础日粮+2000 mg·kg^-1 Zn-Pal(试验Ⅱ组)、基础日粮+4000 mg·kg^-1 Zn-Pal(试验Ⅲ组)4种日粮.整个试验包含预试期7 d,正试期28 d,研究Zn-Pal替代抗生素和ZnO对断奶仔猪生长性能、器官指数、生化指标及抗氧化能力的影响.结果表明:(1)Zn-Pal替代日粮中的抗生素和ZnO后对仔猪的平均日增重及料重比无显著影响(P>0.05);试验Ⅲ组的腹泻率、腹泻指数与对照组的差异不显著(P>0.05),试验Ⅱ组的腹泻率显著高于其他各组(P<0.05).(2)试验Ⅱ、Ⅲ组仔猪心脏、脾脏和肾脏的指数显著低于对照组(P<0.05),胰脏指数显著高于试验Ⅰ组(P<0.05).(3)试验Ⅲ组仔猪血清的总抗氧化能力和铜锌超氧化物歧化酶活性显著高于试验Ⅱ组(P<0.05),但与对照组的差异不显著(P>0.05);试验Ⅱ、Ⅲ组的丙二醛浓度显著低于对照组和试验Ⅰ组(P<0.05).(4)试验Ⅲ组仔猪血清总蛋白和球蛋白的含量显著高于试验Ⅰ组(P<0.05),而白蛋白含量和白球比显著低于对照组(P<0.05);试验Ⅱ、Ⅲ组甘油三酯和总胆固醇的浓度显著低于对照组(P<0.05);对照组的尿素氮浓度显著低于其他各组(P<0.05);试验Ⅲ组的高密度脂蛋白浓度显著高于试验Ⅱ组(P<0.05),低密度脂蛋白浓度显著低于对照组(P<0.05).在本试验条件下,日粮中添加4000 mg·kg^-1 Zn-Pal能够替代饲料中的抗生素和ZnO用于仔猪饲料生产.

To investigate the effects of zinc-bearing palygorskite(Zn-Pal)as an alternative to antibiotic and ZnO on the growth performance and physiochemical condition of postweaning piglets,128 hybrid weaned piglets(Duroc×Landrace×large white)with an average initial body weight of(8.59±0.40)kg at the age of 25 d were randomly divided into 4 groups,with 4 replicates per group,8 piglets per replicate,and equal number of male and female piglets.Piglets in the 4 groups were supplemented with 110 mg·kg^-1 kitamycin and 2000 mg·kg^-1 ZnO(control group),55 mg·kg^-1 kitamycin,1000 mg·kg^-1 ZnO and 2000 mg·kg^-1 Zn-Pal(experimental groupⅠ),2000 mg·kg^-1 Zn-Pal(experimental groupⅡ),and 4000 mg·kg^-1 Zn-Pal(experimental groupⅢ),respectively.This trial started with a pre-test for 7 d and then tested for 28 d.The results showed that(1)dietary supplementation of Zn-Pal instead of anibiotic and ZnO did not significantly affect the average daily gain and feed to gain ratio in piglets(P>0.05);There were no significant differences in the diarrhea rate and diarrhea index between groupⅢand the control(P>0.05),though diarrhea rate in experimental groupⅡwas significantly higher than those of other groups(P<0.05).(2)Indexes of heart,spleen and kidney in groupsⅡandⅢwere significantly lower than those in the control(P<0.05),whereas,pancreas indexes were higher in groupsⅡandⅢthan groupⅠ(P<0.05).(3)Serum total antioxidant capacity and activity of copper-zinc superoxide dismutase were significantly higher in groupⅢthanⅡ(P<0.05),but they were not significantly different between groupⅢand the control(P>0.05);Serum malondialdehyde contents were significantly lower in groupsⅡandⅢthan groupⅠand the control(P<0.05).(4)Serum total protein and globulin contents were significantly higher in groupⅢthanⅠ(P<0.05),while albumin content and albumin to globulin ratio were significantly lower in groupⅢthan the control(P<0.05).Contents of triglyceride and total cholesterol were significantly lower in experimental groupsⅡandⅢthan the control(P<0.05).Serum urea nitrogen content was significantly lower in the control than other groups(P<0.05).Serum high-density lipoprotein content was significantly higher in groupⅢthanⅡ(P<0.05),and low-density lipoprotein content was significantly lower in groupⅢthan the control(P<0.05).Under experimental condition,Zn-Pal supplemented at 4000 mg·kg^-1 is a good alternative to antibiotics and ZnO for piglet feed production.