利用(15)N示踪技术研究尿素在人工瘤胃中的代谢  

METABOLISM OF DIET UREA IN THE RUMEN in vitro BY ^(15)N-TRACER TECHNIQUE

作　　者：高占锋[1,2] 王红云[2] 付才[2] 黄志国[2] 吕林[1,2] 刘彬[1] 赵广永[3] 罗绪刚[1] 

机构地区：[1]中国农业科学院畜牧研究所矿物元素营养研究室,动物营养学国家重点实验室,北京100193 [2]河北省农林科学院遗传生理研究所,河北石家庄050051 [3]中国农业大学动物科技学院,北京100193

出　　处：《核农学报》2011年第2期317-324,共8页Journal of Nuclear Agricultural Sciences

基　　金：河北省自然基金(C2006000742)

摘　　要：通过人工瘤胃短期发酵,采用4×2析因完全随机试验设计,利用15 N标记尿素代替日粮粗蛋白的0%、10%、20%、40%,分别发酵24和48h,研究日粮不同尿素添加量对瘤胃发酵参数的影响及其在瘤胃中的代谢。结果表明:不同尿素添加量和发酵时间对瘤胃pH影响不显著(P>0.05),添加尿素处理的瘤胃液氨态氮浓度在发酵48h时显著高于发酵24h;尿素添加量和发酵时间对颗粒相和液相微生物的含氮量影响不显著(P>0.05);瘤胃食糜各相中的尿素氮与日粮尿素添加量呈显著的正线性相关关系(P<0.01);瘤胃食糜各组分总氮中尿素氮所占的比例与日粮尿素添加量呈显著的正线性相关关系(P<0.01);日粮尿素在瘤胃食糜各组分中的分配数量依次为上清液(54.88%～73.03%)>未消化饲料(27.83%～37.56%)>液相微生物(7.99%～10.18%)>颗粒相微生物(4.5%～6.17%),尿素添加量和发酵时间不改变尿素氮在瘤胃食糜的发展趋势。A completely randomized design involving 4 × 2 factorial arrangement of treatments was used to investigate effects of urea in diet（urea replaced diet CP of 01,0% 2,0% a,nd 40%）and fermentation time（24 and 48h） on rumen fermentation parameters and the metabolism of urea in the rumen in vitro.Results showed that different amendments of urea in diets and fermentation time had no significant effect on pH of rumen digesta（P 0.05）;the concentration of NH3-N,however,was increased significantly from 24 to 48h in each treatment（P 0.01）.There was significantly positive linear correlations between urea nitrogen in fractions of rumen digesta and the quantity of urea in diets（P 0.01）,and between the ratio of urea nitrogen to total nitrogen in fractions of rumen digesta and the quantity of urea in diet.The distribution of diet urea in fractions of rumen digesta followed the order of supernatant fluid（54.88% ～ 73.03%） undigested feed（27.83% ～ 37.56%） liquid-associated microbe（7.99% ～ 10.18%） particleassociated microbe（4.50%～6.17%）The quantity of urea in diets and fermentation time did not affect the trend of the distribution.

关 键 词：15N示踪技术 尿素 微生物蛋白 非蛋白氮 

分 类 号：S816[农业科学—饲料科学]