5株优良抑菌活性乳酸菌对全株玉米青贮品质的影响

为了探讨具有优良抑菌活性的乳酸菌对全株玉米青贮过程不同时期营养品质的影响,进一步验证并筛选出可提高玉米秸秆青贮品质的乳酸菌接种剂,将实验室前期从甘肃各地玉米秸秆青贮饲料中分离筛选获得的5株产酸快、多,且具有抑菌活性的优良乳酸菌分别添加到全株玉米秸秆中进行青贮,共设置6个试验组,分别在青贮第3、7、15、30天测定产物的干物质(DM)、粗蛋白(CP)、可溶性碳水化合物(WSC)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)和氨态氮(NH₃-N)含量及第30 天乳酸(LA)、乙酸(AA)、丙酸(PA)和丁酸(BA)含量。结果显示,发酵30 d后,5个处理组的DM、CP、ADF和LA含量显著高于对照组(P<0.05),NH₃-N和WSC含量显著低于对照组(P<0.05),B3-1组NDF显著高于对照组(P<0.05),但与其他处理组差异不显著(P>0.05),B3-1和B5-2组AA含量显著高于对照组(P<0.05),但与其他处理组差异不显著(P>0.05);各组DM、CP、WSC含量均随发酵时间延长而降低,而ADF、NDF和NH₃-N含量均随发酵时间的延长而升高;B3-1组在玉米秸秆全株青贮发酵各期的发酵品质和营养品质最优。以上结果表明5株乳酸菌均能显著改善青贮饲料发酵品质,其中植物乳杆菌B3-1的效果最好。

Effect of 5 strains of Lactic acid bacteria with antibacterial activity on the corn silage quality

To investigate the effect of lactic acid bacteria (LAB) with antibacterial activity on the quality of corn silage during ensiling,and screen LAB inoculant that could improve the quality of silage,5 strains of LAB (B1-7,B2-3,B3-1,B5-2,E2-3) isolated from corn silage across Gansu province were added to make corn silage,the contents of dry matter (DM),crude protein (CP),water soluble carbohydrates (WSC),neutral detergent fiber (NDF),acid detergent fiber (ADF),ammonia nitrogen (NH3-N),lactic acid (LA),acetic acid (AA),propionic acid (PA) and butyric acid (BA) were analyzed.Results showed that for silage at 30 days,the content of DM,CP,ADF and LA was significantly increased in 5 LAB strains treatment groups compared with the control group,and the content of NH3-N and WSC was decreased.The NDF content in silage inoculated with the B3-1 LAB strain was significantly higher than the control (P＜0.05),with the other 4 LAB strains being intermediate,while the content of AA in B3-1 and B5-2 treated silages was significantly higher than the control but not the other 3 treatment groups.Along with the fermentation time the content of dry matter,crude protein,water soluble carbohydrates in silages of each group was decreased and the content of ADF,NDF and NH3-N increased.Overall,the silages inoculated with the B3-1 strain showed best fermentation quality and nutritive value characteristics.These results indicated that all added LAB strains improved the quality of silage,with Lactobacillus plantarum B3-1 being the most effective.