Abstract: In order to improve the forage utilization degree of broccoli stems and leaves, this experiment was conducted to investigate the feeding quality, fermentation quality, microbial dynamics and nitrate and nitrite contents of broccoli under natural stacking conditions. The experiment was set up with 4 stacking treatments:0 d (T0), 1 d (T1), 2 d (T2) and 3 d (T3), and the fermentation quality of silage was analyzed at 30, 60 and 90 days. The results showed that with the increase of stacking time, the content of non-structural carbohydrates decreased continuously (P<0.05). With the prolongation of silage time, the contents of ammonia nitrogen/total nitrogen and acetic acid were increased (P<0.05), but the content of lactic acid was not significantly changed (P>0.05), and both V-Score and Kaiser showed a decreasing trend. Among all the treatments, T3 had the lowest score. It can be seen from the indexes that the silage with 0~2 d stacking time for 30~60 days silage can get better fermentation quality.

Key words: Broccoli waste, Stacking time, The quality of silage, Nitrate, Nitrite

摘要： 为提高西兰花尾菜的饲料化利用程度，本试验探究了西兰花尾菜在自然堆放条件下的饲用品质，青贮后的发酵品质、微生物动态以及硝酸盐和亚硝酸盐含量。试验设置堆放0 d （T0）、1 d （T1）、2 d （T2）和3 d （T3）共4个处理，青贮30、60、90 d时进行发酵品质分析。结果表明，随着堆放时间的延长，尾菜非结构碳水化合物含量持续下降（P<0.05）。随着青贮时间的延长，氨态氮/总氮、乙酸含量升高（P<0.05）、乳酸含量变化不显著（P>0.05），V-Score和Kaiser得分均呈降低趋势，T3得分最低。综合各项指标可知：采用堆放时间为0~2 d的西兰花尾菜青贮30~60天可获得发酵品质较优良的青贮饲料。

关键词: 西兰花尾菜, 堆放时间, 青贮品质, 硝酸盐, 亚硝酸盐