摘要
用3头装有永久性瘘管的中国荷斯坦牛,采用3×3拉丁方设计对蜡熟期、乳熟期和乳熟前期的玉米青贮的NDF和ADF进行了瘤胃降解率及其日粮对瘤胃发酵内环境的影响进行了研究。结果表明,乳熟期玉米青贮NDF在瘤胃中的有效降解率(30．77％)分别高于蜡熟期(28．59％)和乳熟前期(26．71％,P<0．05),蜡熟期和乳熟前期之间差异不显著。蜡熟期(25．73％)和乳熟前期(25．23％)玉米青贮ADF有效降解率均高于乳熟期(23．39％,P<0．05),但蜡熟期和乳前熟期之间没有明显差异。饲喂乳熟前期、乳熟期、蜡熟期玉米青贮组成的日粮的奶牛瘤胃液pH值变动范围分别为6．37～7．27,6．37～6．97,6．33～7．27;NH3-N浓度的平均值分别为33．32 mg／dl, 38．87 mg／dl,34．53 mg／dl;乙酸、丙酸和丁酸浓度分别为49．48,12．58,4．54 mmol／L、49．83,10．28,6．41 mmol／L和44．24,9．32,5．43 mmol／L。表明三组牛瘤胃pH值、NH3-N和VFA浓度没有显著性差异(P>0．05)。
Three rumen fistulated Holstein cows were used in a 3×3 Latin square experimental design to determine the rumen degradability of NDF and ADF of corn silage at premilk stage, milk stage and dough stage and the effect of diets on rumen environment of cows. The result showed that the effective degradability （ED） of NDF in corn silage harvested at milk stage （30. 77%） was greater than that at dough stage （28. 59%） and premilk stage （26. 71%） （P〈0. 05）, there was no significant difference between dough stage and premilk stage. The ED of ADF in corn silage harvested at dough stage （25.73 %） and premilk stage （25. 23%） were significantly higher than that at milk stage （23.39%） （P〈0.05）, there was no difference between dough stage and premilk stage. The rumen pH value of cows fed diets containing corn silage harvested at premilk stage, milk stage and dough stage ranged from 6. 37 to 7. 27, 6. 37 to 6.97, 6. 33 to 7. 27; the rumen NH3-N concentrations were 33. 32 mg/dL, 38. 87 mg/dL, and 34.53 mg/dL, respectively. The acetate, propionate, and butyrate concentration were 49. 48, 12. 58, 4. 54 mmol/L; 49. 83, 10. 28, 6.41 mmol/L; and 44.24, 9.32, 5.43 mmol/L, respectively. No significant difference was observed for pH value, and NH3-N and VFA concentration in the rumen of cows （P〉0.05）.
出处
《中国牛业科学》
2006年第5期32-36,共5页
China Cattle Science
基金
"十五"国家乳业专项-"东北农区乳业现代化生产技术集成与产业化示范"
课题编号:2002BA518A09
关键词
奶牛
玉米青贮
结构性碳水化合物
瘤胃发酵
Dairy cattle
Corn silage
Structural carbohydrate
Rumen fermentatio
作者简介
苗树君（1956-），男，黑龙江绥化人，教授，主要从事反刍动物营养与饲养教学和研究。
