不同日粮氮水平对山羊氮代谢和微生物蛋白质合成的影响  

Effects of Dairy Crude Protein levels on Nitrogen Metabolism and Microbial Protein Synthesis in Growing Inner Mongolia White Cashmere Goats

作　　者：樊艳华[1,2] 孙海洲 桑丹 李胜利 张春华 吴宝升[1,2] 

机构地区：[1]内蒙古农业大学动物科学学院,内蒙古呼和浩特010018 [2]内蒙古自治区农牧业科学院动物营养与饲料研究所,内蒙古呼和浩特010031

出　　处：《中国畜牧杂志》2015年第1期28-32,共5页Chinese Journal of Animal Science

基　　金：国家自然科学基金(31260563);国家公益性行业(农业)科研专项(201303059);国家公益性行业(农业)科研(201303062);内蒙古农牧业科技创新基金项(2013CXJJM05);国家绒毛用羊产业技术体系建设(CARS-40-12)

摘　　要：本试验旨在探讨不同日粮氮水平对内蒙古白绒山羊氮代谢和微生物蛋白质合成(MCP)的影响,以达到提高氮利用率,减少环境污染和饲料资源的浪费。试验选用9只体况良好、体重为(43.83±2.95)kg,装有瘤胃瘘管的内蒙古白绒山羊,按体重随机分为3组,每组3只。日粮分为低氮7.5%、中氮10.5%、高氮13.5%3个氮水平。试验使用常规试验方法分析测定粪尿血液等生化指标,通过全收尿法和尿嘌呤衍生物法估测MCP。结果表明:随着氮水平增加,氨氮(NH3-N)浓度、氮摄入量、尿氮排出、尿中尿素氮(UUN)和MCP显著增加(P<0.05),干物质采食量(DMI)显著降低(P<0.01);沉积氮占总摄入氮的比例在中氮组最高,MCP在高氮组最高。综上所述,适当降低日粮氮水平可减少粪尿氮排放,提高反刍动物氮利用率。This experiment was conducted to study the effects of dairy crude protein levels on nitrogen metabolism and microbial protein synthesis （MPS） in growing Inner Mongolia White Cashmere Goats. Nine Inner Mongolia White Cashmere Goats （43. 83±2.95kg of initial BW） fitted with ruminal cannulas were blocked into 3 groups by initial BW. Goats were fed dietary crude protein levels （CP） of 7.5 （LOW）, 10.5 （MID）, and 13.5% （HIGH） CP with similar amounts of metabolizable energy （ME） as dry matter intake. Conventional test methods were selected, for analysis of determination of feces N, urine N, UUN and PUN, and the urinary excretion of purine derivatives method was used to estimate microbial protein synthesis. With the increase of the diet nitrogen levels, the ruminal concentration of NH3-N, nitrogen （N） intake, feces N, urine N, UUN and MCP increased gradually （P〈0.05）, whereas dry matter intake decreased （P〈0.01）. N retention as a proportion of N intake was higher in fed diet MID compared to LOW and HIGH （P〈0.05）. To sum up, the appropriate reduction of diet N was benefit to improve the utilization of N when the demand of microbial protein of animal was met.

关 键 词：日粮氮水平 微生物蛋白质的合成 氮利用率 尿嘌呤衍生物法 山羊 

分 类 号：S827.5[农业科学—畜牧学]