不同切碎长度和发酵方式对全株饲用谷子青贮质量的影响

Effect of Various Cutting Lengths and Fermentation Models on Quality of Whole Hybrid Foxtail Silage

本研究旨在探索不同切碎长度和发酵方式对全株饲用青贮谷子质量的影响。采用2×3双因子试验设计,切割长度分别为1.5 cm、2.5 cm和3.5 cm,发酵方式分为复合菌剂发酵和乳酸菌发酵两个类型,每处理3个重复。常温发酵40 d后取样,进行感官评定,分析基础养分,测定挥发性成分。结果表明,随着切碎长度增加,气味评分和总分总体呈降低趋势,中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)含量呈增加趋势,丁酸含量显著增加;相比乳酸菌发酵组,复合菌剂发酵组整体气味评分和乳酸含量较高,pH值和NDF、ADF含量较低。综上,不同切碎长度和发酵方式对于全株饲用谷子青贮质量均有显著影响。降低切碎长度和使用复合菌剂发酵均有助于促进纤维分解,减少丁酸产量,改善青贮感官评分。

In order to study the effects of various cutting lengths and fermentation models on quality of whole hybrid foxtail silage,a 2×3 double-factor assay was designed.Fresh whole hybrid foxtail was cut separately at the sizes of 1.5 cm,2.5 cm and 3.5 cm,and then fermented and cultured under two different models consisting of complex microbial fermentation and lactobacillus fermentation.The 6 treatments were repeated three times.After 40 days of fermentation at room temperature,sensory evaluation and fundamental nutrients measurement were conducted and volatile constituent percentages were measured.The results showed that with the increase of cutting length,odor score and sensory score decreased,neutral detergent fiber(NDF)and acid detergent fiber(ADF)contents showed increasing trend,and butyric acid percentage increased significantly,in general.In comparison to the lactobacillus inoculant treatments,the complex microbial inoculant treatments had higher odor scores and lactic acid contents,lower pH values,NDF and ADF contents.It was concluded that both cutting length and fermentation model had obvious effects on quality of whole hybrid foxtail silage.Shorter cutting lengths and application of complex microbial fermentation would help promoting decomposition of fiber,reducing production of butyric acid and improving sensory score of silage.