热带地区作物秸秆类青贮饲料的调制与发酵品质

为了有效利用农作物副产品资源，解决热带旱季家畜饲料短缺的问题，本试验对非洲产玉米秸秆和甘蔗秸秆中分离的野生乳酸菌的特性以及高品质的青贮发酵技术进行了分析和探讨。两种农作物秸秆的试验处理区均设定为无添加剂组、乳酸菌剂组、纤维素酶组和乳酸菌剂及纤维素酶组合处理组。收获后的新鲜玉米秸秆和甘蔗秸秆的干物质含量分别为43%和26%，为青贮发酵的适宜水分含量范围。玉米秸秆和甘蔗秸秆的中性洗涤纤维含量分别为65 %和76 %，粗蛋白含量两者相近，显示为6%~7%。野生乳酸菌群落包括植物乳杆菌、短乳杆菌、西伯利亚魏氏菌、拉氏乳球菌和酸性乳球菌。在两种作物上的菌落数变化范围为每克鲜样的菌数为102至106。植物乳杆菌和魏氏菌分别是存在于玉米秸秆和甘蔗秸秆中的主要菌种。短乳杆菌和乳酸片球菌是存在于两种农作物秸秆中的常见菌株。添加乳酸菌和纤维素酶后，青贮饲料pH值下降，乳酸含量上升，有效地改善了发酵品质。两种秸秆在青贮发酵过程中均没有发生明显的营养损失，显示出良好的贮藏特性。本研究证实，这两种农作物秸秆均可以制备成高品质的青贮饲料，并能很好地保存饲料中的营养物质。

Silage Preparation and Fermentation Quality of Crop By-product in Tropics

To effectively utilize crop by-product resources to cover the shortage of animal feed during the dry season in tropics, the characteristics of lactic acid bacteria (LAB) isolated from corn stover and sugarcane top and their silage fermentation with high quality were analyzed. Both silages were prepared with control, LAB inoculant, cellulase enzyme and their combination. After harvesting, the dry matter (DM) of fresh corn stover and sugar can top were 43% and 26%, and it is adequate moisture range for silage fermentation. The neutral detergent fiber were 65% for corn stover and 76% for sugarcane top on a DM basis, while their crude protein (CP) contents were similar, ranging from 6%~7% of DM. The natural LAB communities including Lactobacillus plantarum, Lactobacillus brevis, Weissella cibaria, Lactococcus latcis and Pediococcus acidilactici. were present with 102 to 106 colony-forming unit/g of FM on both crops by-products. Lactobacillus plantarum and Weissela cibaria were the dominant LAB population in corn stove and sugarcane top, respectively. Lactobacillus brevis and Pediococcus acidilactici were the frequent isolates from both crops by-products. When their silages inoculated with LAB and cellulase, the fermentation quality was improved with lower pH value and higher lactic acid content than those of control. Both crop by-products can be used to produce high quality silage and preserve nutrients in the feed well.