添加单宁酸对木薯叶青贮品质和有氧稳定性的影响

Effect of tannic acids on the fermentation quality and aerobic stability of cassava foliage

为了改善木薯(Manihot esculenta)叶青贮品质,本研究分析了单宁非光合酸对木薯叶青贮品质及营养成分的影响,以确定青贮木薯叶最适合的单宁酸添加量。本研究以华南7 号木薯幼嫩茎叶为原料进行青贮试验,设对照组和添加0.5%、1%、2%的单宁酸处理组,30d后分析木薯叶青贮饲料发酵品质、有氧稳定性以及主要营养成分含量。结果表明,木薯叶直接青贮品质较差,添加单宁酸处理可以提高青贮饲料的乳酸含量,降低pH 和丁酸含量(P<0.05),提高有氧稳定性,其中添加1%单宁酸处理组pH 最低、乳酸含量最高、青贮评分最高;同时可以提高粗蛋白(crude protein,CP)含量,降低中性洗涤纤维(neutral detergent fiber,NDF)和酸性洗涤纤维(acid detergent fiber,ADF)含量(P<0.05),提高了饲料相对值(relative feed value,RFV),其中添加1%单宁酸处理组RFV 最高。因此,添加单宁酸可以提高木薯叶青贮品质和有氧稳定性,并提高营养价值。综合考虑,推荐单宁酸适宜添加浓度为1%。

The objective of this study was to evaluate the effects of tannic acids on the fermentation quality,aerobic stability, and nutrient content of cassava (Manihot esculenta) foliage silage and to determine the optimal tannic acid addition rate. Experimental treatments included a control (CK) and three treatments of different tannic acid addition ratios (0.5%,1%,2% of fresh weight).Silos were opened after 30 days of ensiling and fermentation quality,aerobic stability,and chemical composition were analyzed.Results showed that the addition of tannic acids increased lactic acid content (LA),decreased pH and butyric acid content (P < 0.05),and improved aerobic stability relative to the control.In the 1% addition treatment,pH was lower and LA content and silage scores were higher than in other treatments.Additionally,fiber content decreased (P < 0.05),and crude protein (CP) and relative feed value (RFV) of tannic acid treatments increased.We found that the RFV of the 1% addition treatment was significantly higher than in other treatments.In conclusion,tannic acid addition improves the fermentation quality,aerobic stability,and nutrient value of cassava foliage silage,and results suggest that a 1% tannic acid addition is the most appropriate treatment.