不同生长期饲用油菜的营养价值和青贮发酵品质

为了为饲用油菜的牧草化利用提供数据参考,本研究分析了蕾苔期、结夹初期和结夹末期饲用油菜(Brassica napus)植株的营养价值及青贮过程中品质变化规律。结果表明:1)随着生长期变化,饲用油菜的总能、粗脂肪、粗蛋白质、硫甙含量和相对饲喂价值均呈现先下降后上升的规律;蕾苔期油菜的可溶性碳水化合物显著高于结荚初期和结荚末期(P <0.05),而中性洗涤纤维和酸性洗涤纤维含量极显著低于结荚初期和结荚末期(P <0.01);结夹末期植株中粗脂肪含量达到16.02%,极显著高于蕾苔期和结荚初期(P <0.01)。2)不同生长期油菜青贮后pH、乙酸含量、丁酸含量、氨态氮/总氮以及V-Score评分差异显著(P <0.05)。同一生长期油菜不同青贮时间点的pH、乳酸含量、丁酸含量、V-Score评分差异显著(P <0.05)。蕾苔期、结荚初期油菜青贮过程中乳酸、乙酸含量迅速升高,到60 d时达到最高,各处理组内含量差异显著(P <0.05)。结荚期末油菜青贮后感官品质、V-Score评价级别都比较低。综上所述,蕾苔期和结荚初期饲用油菜营养价值较高且适宜青贮,单...

Nutritional value and silage fermentation quality of forage cole in different growth periods

In this paper,we studied the nutritional value,silage nutritional quality,and fermentation quality changes of rapeseed in the lace,initial,and final stages to provide a reference for the utilization of forage rape.The results showed that:1)with the change in growth period,the GE,EE,CP,thioside content,and RFV of forage rapeseed decreased first and then increased.The concentration of soluble carbohydrates in lace rapeseed were significantly higher than that of the initial stage and final stages,while the content of NDF and ADF were significantly lower than that of the initial and final stages(P<0.01).The ether extract content in final-stage plants reached 16.02%,which was significantly higher than that of lace-stage and initial-stage plants(P<0.01).2).The pH,acetic acid,butyric acid,ammonia nitrogen/total nitrogen,and V-Scores of rapeseed in the different growth stages were significantly different(P<0.05).The pH,lactic acid content,butyric acid content,and V-Scores of rapeseed at different silage times were also significantly different(P<0.05).The content of lactic acid and acetic acid in rapeseed during the lace and initial stages increased rapidly,reached maximum values at 60 days,and the content of each treatment group was significantly different(P<0.05).The sensory quality and V-Score evaluation of final-stage rapeseed in silage were relatively low.In summary,forage rapeseed at the lace and initial stages has high nutritional value and is suitable for silage,and the silage time is preferably 30 to 45 days.