Sun Lin, Wang Zhijun, Gentu Ge, Jia Yushan, Hou Meiling, Cai Yimin
Key Laboratory of Grassland Resources, Ministry of Education, P.R. of China, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot 010019, China.
Inner Mongolia Academy of Agricultural Sciences & Animal Husbandry, Hohhot, Inner Mongolia, 010030, China.
Asian-Australas J Anim Sci. 2019 Jun;32(6):815-825. doi: 10.5713/ajas.18.0514. Epub 2018 Nov 27.
To effectively use corn stover resources as animal feed, the changes in microbial population and chemical composition of corn stover during field exposure, and their silage fermentation and in vitro digestibility were studied.
Corn cultivars (Jintian, Jinnuo, and Xianyu) stovers from 4 random sections of the field were harvested at the preliminary dough stage of maturity on September 2, 2015. The corn stover exposed in the field for 0, 7, 15, 30, 60, 90, and 180 d, and their silages at 60 d of ensiling were used for the analysis of microbial population, chemical composition, fermentation quality, and in vitro digestibility. Data were analyzed with a completely randomized 3×6 [corn stover cultivar (C)×exposure d (D)] factorial treatment design. Analysis of variance was performed using SAS ver. 9.0 software (SAS Institute Inc., Cary, NC, USA).
Aerobic bacteria were dominant population in fresh corn stover. After ensiling, the lactic acid bacteria (LAB) became the dominant bacteria, while other microbes decreased or dropped below the detection level. The crude protein (CP) and water-soluble carbohydrate (WSC) for fresh stover were 6.74% to 9.51% and 11.75% to 13.21% on a dry matter basis, respectively. After exposure, the CP and WSC contents decreased greatly. Fresh stover had a relatively low dry matter while high WSC content and LAB counts, producing silage of good quality, but the dry stover did not. Silage fermentation inhibited nutrient loss and improved the fermentation quality and in vitro digestibility.
The results confirm that fresh corn stover has good ensiling characteristics and that it can produce silage of good quality.
为有效利用玉米秸秆资源作为动物饲料，研究了田间暴露期间玉米秸秆微生物种群和化学成分的变化及其青贮发酵和体外消化率。
于2015年9月2日在乳熟初期从田间4个随机区域收获玉米品种（金田、金诺和先玉）的秸秆。将田间暴露0、7、15、30、60、90和180天的玉米秸秆及其青贮60天的青贮料用于微生物种群、化学成分、发酵品质和体外消化率分析。数据采用完全随机的3×6[玉米秸秆品种（C）×暴露天数（D）]析因处理设计进行分析。使用SAS 9.0软件（美国北卡罗来纳州卡里市SAS研究所）进行方差分析。
新鲜玉米秸秆中需氧菌为优势种群。青贮后，乳酸菌成为优势菌，而其他微生物减少或降至检测水平以下。新鲜秸秆的粗蛋白（CP）和水溶性碳水化合物（WSC）在干物质基础上分别为6.74%至9.51%和11.75%至13.21%。暴露后，CP和WSC含量大幅下降。新鲜秸秆干物质含量相对较低，但WSC含量和乳酸菌数量较高，能生产出优质青贮料，而干燥秸秆则不能。青贮发酵抑制了养分损失，提高了发酵品质和体外消化率。
结果证实新鲜玉米秸秆具有良好的青贮特性，能够生产出优质青贮料。
