【摘要】 采用稳定同位素(15N-Gly)示踪技术和氮平衡试验,比较研究了外源代谢调节物(黄芪组方浓缩物、半胱胺)对PIC肥育猪生长性能、体蛋白动态代谢和氮沉积的影响。选用32头体重59.82±1.32kg的PIC商品猪,随机分成4个处理组,CON组、NCAE组、CAE组和CS组。每处理设4个重复,每重复2头猪。试验结果表明:(1)黄芪组方浓缩物和半胱胺均明显提高肥育猪的生长性能,其中基础日粮+半胱胺70mg/kg组(CS组)显著提高肥育猪日采食量(P<0.05),基础日粮+黄芪组方浓缩物250mg/kg组(CAE组)和基础日粮+非稳定化处理黄芪组方浓缩物250mg/kg组(NCAE组)显著提高饲料利用率(P<0.05),从而使肥育猪日增重均显著提高(P<0.05)。(2)黄芪组方浓缩物和半胱胺均显著增加肥育猪体蛋白沉积速率、显著提高氨基酸利用效率和生物学效价(P<0.05);黄芪组方浓缩物显著提高可消化氨基酸用于合成体蛋白质的速率(P<0.05),降低内源尿氮排泄速率。(3)黄芪组方浓缩物和半胱胺调控体蛋白沉积的强度和途径不同:半胱胺主要通过降低体蛋白降解速率26.71%,增加体蛋白沉积速率63.53%(P<0.05);黄芪组方浓缩物通过降低体蛋白降解速率和提高体蛋白合成速率,共同增加体蛋白沉积,与对照组相比,NCAE和CAE组体蛋白质降解速率分别降低了24.84%和13.66%,体蛋白合成速率分别提高了22.86%和19.18%。(4)黄芪组方浓缩物和半胱胺均可改善氮代谢,体现在CS组显著提高氮的净利用率和生物学效价(P<0.05),CAE组极显著改善沉积氮、氮的净利用率和生物学效价(P<0.01),NCAE组显著提高氮的净利用率和生物学效价(P<0.05)。更多还原

【Abstract】 32 PIC pigs,weighted 59.82±1.32 kg on average,were subjected randomly to 4 treatments for determining the effects of extrogenous metabolism-regulating agents on pig performance,protein turn-over and nitrogen retention by using isotope(15N-Gly) technique and nitrogen balance trial.The 4 treatments were:(1) basal diet;(2) basal diet plus cysteamine(70mg/kg,CS group);(3) basal diet plus non-stable astragalus extracts 250mg/kg(NCAE group);(4) basal diet plus stably astragalus extracts 250mg/kg(CAE group).Astragalus extracts and cysteamine,especially NCAE,redounded to increase pig performance,especially increase average day gain(P<0.05).Both astragalus extracts and cysteamine accelerated protein aggradation rate and amino acid utilization rate,as well as biological value.Astragalus extracts helped to accelerate the synthesis rate of amino acid into body protein and reduce the excretion rate of endogenous urine nitrogen.The mechanism of increasing protein deposition of cysteamine is reducing body protein degradation rate(26.71% reduction,compared to control group),while that of astragalus extracts is bilateral,reducing protein degradation rate(24.84% and 3.66% reduction for NCAE and CAE) and accelerating protein synthesis rate(22.86% and 19.18% increase for NCAE and CAE).Both astragalus extracts and cysteamine contributed the increasing nitrogen retention,net nitrogen utilization and biological value.更多还原