应用^(15)N和嘌呤估测肉羊微生物N产量的研究  

Study on Microbial N Yield Measured with ^(15)N and Purine Bases in Mutton Sheep

作　　者：马涛[1] 刁其玉[1] 邓凯东[2] 姜成钢[1] 屠焰[1] 张乃锋[1] 王永超[1] 刘洁[1] 赵一广[1] 

机构地区：[1]中国农业科学院饲料研究所农业部饲料生物技术重点实验室,北京100081 [2]金陵科技学院动物科学与技术学院,南京210038

出　　处：《畜牧兽医学报》2012年第12期1910-1916,共7页ACTA VETERINARIA ET ZOOTECHNICA SINICA

基　　金：国家现代农业肉羊产业技术体系专项资金(CARS-39);公益性行业科研专项"饲料营养价值与畜牧饲养标准研究与应用"(200903006-03)

摘　　要：本试验通过比较2种微生物标记物15 N和嘌呤(Purine bases,PB)估测肉羊瘤胃微生物N产量的效果,旨在建立不同方法之间的内在联系,为准确地估测肉羊微生物N提供依据。试验选用12只平均体质量为(41.3±2.8)kg的杜寒杂交(杜泊羊×小尾寒羊杂交)绵羊公羔,随机均分为3组,按照自由采食、自由采食量的70%和40%3个干物质采食水平饲喂,试验共持续25d,其中预试期10d,正试期15d,最后5d采集瘤胃食糜和十二指肠食糜并测定15 N和PB。结果表明,瘤胃细菌成分(氮含量、嘌呤含量和嘌呤/氮)不受日粮处理的影响(P>0.05);十二指肠干物质、有机物、非氨氮和嘌呤流量均随日粮饲喂水平的降低显著下降(P<0.05);应用15 N和PB计算得到的微生物N产量均随日粮饲喂水平的降低而显著降低(P<0.05),计算得出的微生物合成效率则均不受日粮处理的显著影响(P>0.05)。15 N测定的微生物N在各处理内的变异性要小于PB测定得到的微生物N,因此应用15 N来测定微生物N能够得到更为准确可靠的结果。Two different microbial markers, 15N and purine bases（PB）, were used in this experi- ment with the purpose to establish the relationship between the two methods and provide a pre- cise way for measuring microbial N yield in mutton sheep. Twelve Dorper （ Small-tailed Han crossbreds, noncastrated male lambs （（41.3±2.8） kg BW） were randomly assigned to three lev- els of dry matter intake： ad libitum intake, 70% or 40% of the ad libitum intake, with four Iambs at each level. The experiment lasted for 25 d （10 d for adaptation and 15 d for trial peri- od）. The ruminal bacterial components （N, purine bases and purine bases/N） were not affected by dietary treatment （P〉0.05）. Duodenal flows of dry matter, organic matter, non-ammonia ni- trogen and PB decreased significantly with decrease of feed intake （P〈0.05）. Microbial N yield measured with either lSN or PB decreased significantly with decrease of feed intake （P〈0.05） whereas the efficiency of microbial synthesis was not affected by dietary treatment for both mark- ers （P〉0.05）. The result indicate that microbial N measured with lSN showed a smaller within- treatment variation than that measured with PB, and thus 15N can be a reliable marker for accu-rately quantifying microbial N.

关 键 词：肉羊 15N 嘌呤 微生物N 

分 类 号：S826.92[农业科学—畜牧学] S815.4[农业科学—畜牧兽医]