北京市周边地区奶牛场玉米青贮饲料瘤胃降解特性对比分析

摘要

The aim of this study was to compare the ruminal degradation characteristics of dry matter (DM) and neutral detergent fiber (NDF) in maize silage feed in dairy farms around Beijing.Three healthy Holstein dairy cows with permanent rumen fistulas were used as experimental animals.Ruminal degradation rate and characteristics of DM and NDF in 72 h in maize silage feed in 9 dairy farms in Changping,Yanqing and Fangshan (3 farms per district) were determined by nylon bag method.The results showed as follows:1) the average value of DM content in maize silage feed in dairy farms in Fangshan was the highest,but those of NDF and acid detergent fiber (ADF) were the lowest;the average values of DM contents in maize silage feed in dairy farms in Changping and Yanqing was close,that of ADF content in dairy farms in Yanqing was the highest,and that of NDF content in dairy farms in Changping was the highest.2) Dairy farm No.2 in Changping had the highest effective degradation rate of DM in maize silage feed,which was 38.47％;dairy farm No.3 in Fangshan had the lowest effective degradation rate of DM in maize silage feed,which was 28.91％;the difference between these two districts was significant (P＜0.05).3) Dairy farm No.1 in Yanqing had the highest effective degradation rate of NDF in maize silage feed,which was 30.18％,and dairy farm No.2 in Fangshan had the lowest value,which was 19.63％;the difference between these two districts was significant (P＜0.05).In conclusion,the degradation characteristics of maize silage feed in different dairy farms around Beiring are different;it is required that balanced diets should be formulated based on nutrient requirement of dairy cows at different growth,development and lactation stages,combined with the actual nutrient composition.%本研究旨在对北京市周边地区奶牛场的玉米青贮饲料中干物质(DM)和中性洗涤纤维(NDF)的瘤胃降解特性进行对比分析.以3头安装永久性瘤胃瘘管的健康荷斯坦奶牛为试验动物,通过尼龙袋法测定昌平区、延庆区和房山区3个区,每个区3个奶牛场的玉米青贮饲料中DM和NDF的72 h瘤胃降解率及瘤胃降解参数.结果显示:1)房山区奶牛场的玉米青贮饲料中DM含量平均值最高,但NDF和酸性洗涤纤维(ADF)含量的平均值最低,昌平区和延庆区的奶牛场DM含量平均值相近,延庆区奶牛场的ADF含量平均值最高,昌平区奶牛场的NDF含量平均值最高.2)昌平区2号奶牛场玉米青贮饲料的DM有效降解率最高,达到了38.47％;房山区3号奶牛场玉米青贮饲料的DM有效降解率最低,仅为28.91％;二者之间差异显著(P＜0.05).3)NDF的有效瘤胃降解率以延庆区1号奶牛场最高,达到了30.18％,而最低的房山区2号奶牛场只有19.63％,二者之间差异显著(P＜0.05).由此可见,北京市周边地区不同奶牛场的玉米青贮饲料在奶牛瘤胃中的降解特性差异较大,应根据奶牛不同生长发育及泌乳阶段的营养需要,结合实际营养成分,合理配比饲粮.