添加不同浓度黑曲霉菌液对饲用苎麻混合青贮品质影响

Effects of Adding Different Concentrations of Aspergillus niger Liquid on the Quality of Mixed Ramie Silage

为了解决苎麻(Boehmeria nivea)木质纤维素含量过多的问题,本试验设计了4个处理,在每千克混合青贮(80%苎麻+18%麦麸+2%蔗糖)中添加不同浓度的黑曲霉(Aspergillus niger)菌液(添加50 mL黑曲霉菌液+150 mL无菌水为处理Ⅰ、添加100 mL黑曲霉菌液+100 mL无菌水为处理Ⅱ、添加150 mL黑曲霉菌液+50 mL无菌水为处理Ⅲ、添加200 mL黑曲霉菌液为处理Ⅳ、添加200 ml无菌水为对照组(CK)),发酵30 d后开包取样分析各项指标。结果显示,添加黑曲霉菌液显著提高了青贮中可溶性碳水化合物、干物质、乳酸和乙酸含量(P<0.05),显著降低了青贮中pH和氨态氮/总氮比值(P<0.05);处理Ⅱ、处理Ⅲ和处理Ⅳ组显著降低了青贮中中性洗涤纤维、酸性洗涤纤维及酸性不溶木质素含量(P<0.05);对处理Ⅱ组样品进行酶活检测发现,随着发酵时间的延长,羧甲基纤维素酶、锰过氧化物酶、漆酶和木聚糖酶4种酶酶活都有不同程度降低。从节约成本角度考虑,处理Ⅱ组是进行木质纤维素降解、青贮品质提高的最佳处理。

In order to solve the problem of excessive lignocellulose content in ramie(Boehmeria nivea),4 treatments were designed in this experiment,adding different concentrations of Aspergillus niger liquid per kilogram of mixed silage(80%ramie+18%wheat bran+2%sucrose):50 mL of Aspergillus niger+150 mL of sterile water were added in treatmentⅠ,add 100 mL of Aspergillus niger+100 mL of sterile water were added in treatmentⅡ,add 150 mL of Aspergillus niger+50 mL of sterile water were added in treatmentⅢ,add 200 mL of Aspergillus niger liquid were added in treatment IV,200 mL of sterile water was added in control group(CK).The samples were unpacked and analyzed after 30 days of ensling.The results showed that,the four treatments all significantly increased water-soluble carbohydrate concent,dry matter,lactic acid and acetic acid(P<0.05),and significantly reduced the pH value and NH 3-N/TN content of mixed silage(P<0.05).GroupⅡ,groupⅢand groupⅣsignificantly reduced neutral detergent fiber,crude fiber,acid detergent fiber and acid detergent lignin content of mixed silage(P<0.05).From the perspective of cost saving,the treatment groupⅡis the best treatment to degrade cellulose and improve the quality of silage.Enzyme activity of the treated groupⅡsamples was analyzed.Four enzymes:carboxymethylcellulase,manganese peroxidase,laccase and xylanase were detected,and the enzyme activity decreased with the extension of fermentation time.With the extension of the fermentation time,the enzyme activity decreased to varying degrees.