C_4饲草在凋萎处理中饲用品质及青贮品质的变化  

Changes to feeding value and fermentation quality of three C_4 grass species during wilting for silage production

作　　者：张文洁[1] 许能祥[1] 董臣飞[1] 

机构地区：[1]江苏省农业科学院畜牧研究所,江苏南京210014

出　　处：《草业学报》2016年第9期173-181,共9页Acta Prataculturae Sinica

基　　金：公益性行业科研专项(201303061);国家科技支撑计划项目(2011BAD17B02-04);国家牧草产业技术体系项目(CARS-35-31)资助

摘　　要：利用象草、高丹草和玉米在江苏南京进行试验,研究3种C4饲草在不同凋萎时间处理中饲用品质和青贮品质的变化,旨在明确C4饲草在凋萎处理中饲用成分和青贮品质的变化规律,并选择出适宜3种饲草青贮的凋萎时间。试验设置了凋萎0(CK),1.5,3.0,4.5,6.0和7.5h共6个处理,分别测定了原料的干物质含量、干物质体外消化率(IVDMD)、非结构性碳水化合物(NSC)、粗蛋白(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)含量等饲用品质性状,以及pH、乳酸(LA)和氨态氮(NH3-N)含量等青贮发酵品质性状。结果表明,3种C4饲草的原料干物质含量随着凋萎时间的延长均持续上升,其中高丹草和玉米水分含量下降显著(P<0.05),而象草凋萎7.5h后水分含量仍高达75.73%,水分散失较慢;3种C4饲草原料的NSC含量均随着凋萎时间的延长持续下降,但其中的可溶性碳水化合物(WSC)和淀粉含量呈现出不同变化趋势,WSC呈现倒"V"型变化,即在凋萎过程中先上升后下降,而淀粉含量则持续下降;不同饲草凋萎青贮品质最佳的凋萎时间不同,象草是凋萎7.5h、玉米是凋萎3.0h、高丹草是凋萎1.5h。The forage nutrient content and fermentation quality of three C4 forage grass species （Pennisetum [urpureum, Sorghum bicolor × Sorghum sudanese and Zea ma ys ） planted in Nanjing, Jiangsu Province, were analyzed after different wilting times, to investigate the patterns of change and formulate scientifically based guidelines for optimal wilting time during silage production. Six wilting treatments （CK, 1.5 h, 3.0 h, 4.5 h, 6.0 h and 7.5 h） were test, and samples from the different wilting treatments were analyzed for feed quality [dry matter content, in vitro dry matter digestibility （IVDMD）, nonstructural carbohydrates （NSC）, crude protein （CP）, neutral detergent fiber （NDF） and acid detergent fiber （ADF） contentsl, and fermentation qual- ity [pH, lactic acid （LA） and NH3-N content] were analyzed. The dry matter content of all three C, forage grass species increased during wilting, the water content of S. bicolorX S. sudanese and Z. mays decreasing rapidly （P〈0.05）, while P. purpureum dried slowly and still retained a water content of 75.73% after wilting for 7.5 h. The NSC content decreased during the wilting period, but the water soluble carbohydrates （WSC） and starch which were the main components of NSC showed different time courses, the pattern of WSC change was like an inverted V, with an increase at the start of the wilting process, and then a decrease, while the starch content showed a steady decrease throughout the test period. The optimal wilting time for three C4 grass species was 7.5 h for P. purpureum, 3.0 h for Z. mays, and 1.5 h for S. bicolor×S, sudanese.

关 键 词：C4饲草 凋萎 青贮 饲用品质 

分 类 号：S816.53[农业科学—饲料科学]