摘要
试验采用体外瘤胃发酵法来研究肉牛日粮中不同比例精料与粗料间的组合效应(AE)。用注射器法将精料与玉米秸秆青贮、谷草以100∶0(CR100),80∶20(CR80),60∶40(CR60),50∶50(CR50),40∶60(CR40),20∶80(CR20),0∶100(CR0)的比例进行组合,分别测定产气量(GP)、干物质消失率(DMD)、氨态氮(NH_3-N)浓度、微生物蛋白(MCP)产量和挥发性脂肪酸(VFA)浓度及其组合效应值,确定最适宜的精粗比。结果表明,1)CR80组合的体外发酵GP最高,组合效应值最大;CR100组合的DMD最高;而CR50组合的单项组合效应值最大,NH_3-N浓度和MCP产量最高,产生了最大正组合效应。2)乙酸浓度随精料比例的降低呈先上升后下降的趋势,丙酸和丁酸浓度则随精料比例的下降而降低。3)综合分析各组合的多项组合效应指数(MFAEI),CR50组合最大(AE_(24h)0.56,AE_(48h)0.67,AE_(72h)1.00)。因此,在本试验条件下精粗比为50∶50的组合最有利于瘤胃发酵。
The experiment was conducted to determine the associated effects（AE） between concentrate and roughage in beef cattle diets by in vitro rumen fermentation technology.Concentrate was mixed with roughage in ratio of 100 ∶ 0（CR100）,80 ∶ 20（CR80）,60 ∶ 40（CR60）,50 ∶ 50（CR50）,40 ∶ 60（CR40）,20 ∶ 80（CR20）,0 ∶ 100（CR0） by the method of syringe,measured the gas production（GP）,dry matter disappearance rate（DMD）,ammonia concentration（NH_3-N）,microbial protein production（MCP） and volatile fatty acid concentration（VFA） and its associated effects value to screen the optimal combination.The results showed that the GP and associative effect value（AE） of group CR80 was highest,group CR100 had the highest DMD,and CR50 had the highest single associative effect index and the highest NH3-Nconcentration,MCP production and biggest positive associative effect.In addition,concentrations of acetic acid decreased with the levels of concentrate reduction and concentrations of propionic acid and butyric acid were decreased with the levels of concentrate reduction.Furthermore,the multiple factors associative effect index（MFAEI） showed that the maximum positive associative effect（AE24h0.56,AE48h0.67,AE72h1.00） was produced when the ratio of concentrate-forage was 50 ∶ 50.Therefore,our results suggested that the combination of concentrate-roughage at ratio of 50： 50 had most beneficial rumen fermentation.
出处
《畜牧与兽医》
北大核心
2017年第11期36-41,共6页
Animal Husbandry & Veterinary Medicine
基金
公益性行业(农业)科研专项(201503134)
国家现代农业(肉牛)产业技术体系建设专项资金(CARS-38)
河北省科技厅项目(172276225D)
关键词
精料
玉米秸秆青贮
谷草
组合效应
concentrate
corn stalks silage
millet straw
associative effect
