低水平聚天门冬氨酸锌对生长猪生长性能、血液指标、组织器官锌沉积及锌排放的影响

Effects of Low Levels Zinc Polyaspartic Acid on Growth Performance,Blood Parameters,Tissue and Organ Zinc Accumulations and Zinc Emission of Growing Pigs

本试验旨在通过研究聚天门冬氨酸锌(PASP)对生长猪的生长性能、营养物质表观消化率、血清指标、组织器官锌沉积及锌排放的影响,探讨聚天门冬氨酸锌对硫酸锌的替代效果。试验选用体重相近[(31.73±3.50) kg]的(杜×长×大)三元杂交猪90头,随机分为3组,每组6个重复,每个重复5头猪。对照组锌水平及锌源为80 mg·kg^-1一水硫酸锌(ZnSO4·H2O),试验Ⅰ组与Ⅱ组锌水平及锌源分别为60与40 mg·kg^-1聚天门冬氨酸锌;试验预试期7 d,正试期30 d。结果表明:1)试验组与对照组平均日增重、料重比及腹泻率均无显著差异(P>0.05)。2)试验Ⅰ组和Ⅱ组钙(Ca)消化率显著高于对照组(P<0.05),粗蛋白质(CP)、粗脂肪(EE)、粗纤维(CF)、粗灰分(Ash)及磷(P)表观消化率在各组间无显著差异(P>0.05),试验Ⅰ组锌表观消化率显著高于对照组和试验Ⅱ组(P<0.05)。3)试验Ⅰ组和Ⅱ组粪锌水平分别比对照组降低了21.65%和30.87%,差异显著(P<0.01)。4)对照组血清中谷丙转氨酶(ALT)活性显著高于试验Ⅰ组和Ⅱ组(P<0.05),试验Ⅰ组球蛋白(GLB)水平显著高于对照组和试验Ⅱ组(P<0.05),血糖(GLU)、总蛋白(TP)、白蛋白(ALB)、总胆固醇(TC)及碱性磷酸酶(AKP)等指标在各组间差异不显著(P>0.05)。5)各组间肝、肾、胰、脾、骨骼、毛发、背最长肌中锌的沉积量均无显著差异(P>0.05),试验Ⅰ组和Ⅱ组血清锌浓度显著高于对照组(P<0.05)。综上所述,本试验条件下,饲粮中添加40 mg·kg^-1聚天门冬氨酸锌即可满足该阶段猪的生长需要,并显著降低粪中锌的含量,进而证明聚天门冬氨酸锌在生长猪饲粮中可替代高剂量硫酸锌且有一定的减排作用。

This experiment was conducted to study the effects of zinc polyaspartic acid(PASP)monohydrate on growth performance,nutrient apparent digestibility,serum indexes,tissue and organ zinc accumulations and zinc emission of growing pigs,and to determine the substitution effect of zinc polyaspartic acid for zinc sulfate.Ninety Duroc×Landrace×Large White growing pigs with the body weight of(31.73±3.50)kg were randomly assigned into 3 groups with 6 replicates per group and 5 pigs per replicate.The zinc level and source of the control group was 80 mg·kg-1 zinc sulfate,while groupⅠand groupⅡwere 60 and 40 mg·kg-1 zinc polyaspartic acid monohydrate,respectively.Pre-trial period was 7 days,and formal experiment period was 30 days.The results showed as follows:1)There was no significant difference in average daily gain,feed to weight ratio and diarrhea rate among control group and test groups(P>0.05).2)The calcium(Ca)apparent digestibilities of test group I and test groupⅡwere significantly higher than that of the control group(P<0.05);There was no significant difference among groups in apparent digestibility of crude protein(CP),crude fat(EE),crude fiber(CF),crude ash(Ash)and phosphorus(P)(P>0.05).The apparent digestibility of zinc in the test groupⅠwas significantly higher than those of the control group and the test groupⅡ(P<0.05).3)Compared with the control group,the fecal zinc content in the test groupⅠandⅡwere decreased by 21.65%and 30.87%,respectively,and the difference was significant(P<0.01).4)The glutamate transaminase(ALT)activity of control group was significantly higher than those of test groupⅠandⅡ(P<0.05),the globulin(GLB)level of test groupⅠwas significantly higher than those of control group and test groupⅡ(P<0.05),the indexes of blood glucose(GLU),total protein(TP),albumin(ALB),total cholesterol(TC)and alkaline phosphatase(AKP)were not significantly different among groups(P>0.05).5)There were no significant difference of the zinc accumulations in liver,kidney,spleen,pancreas,bone,hair,longgissimus dorsi among groups(P>0.05),the serum zinc concentrations of test groupⅠandⅡwere significantly higher than that of control group(P<0.05).In summary,under this experimental condition,40 mg·kg-1 zinc polyaspartic acid monohydrate could satisfy the needs of growing pigs at this stage,the fecal zinc content was significantly reduced,thus proving the feasibility of adding polyaspartic zinc instead of high dose zinc sulfate in growing pigs’feed,and the emission reduction of zinc.