复合菌种发酵玉米秸秆的效果评定及筛选

Evaluation and Screening of The Effect of Compound Bacteria on Fermentation of Corn Straw

试验以不同复合菌种发酵后的玉米秸秆作为发酵底物,进行瘤胃体外发酵试验并测定相关指标,结合各指标以筛选出最优的复合菌种。试验分为对照组(CON)、黑曲霉菌+地衣芽孢杆菌组(HD)、地衣芽孢杆菌+黄孢原毛平革菌组(DB)、黑曲霉菌+黄孢原毛平革菌组(HB),每个处理组3个重复,于室温下密封发酵21 d后开袋取样,通过感官鉴定和发酵指标评定,并采用瘤胃体外发酵方法,测定产气参数、发酵参数和体外消化率等指标,评价不同复合菌种对玉米秸秆的发酵效果。结果表明,HB、DB组的粗纤维、中性洗涤纤维、酸性洗涤纤维含量均显著低于CON组(P<0.05)。HB组合中酸性木聚糖酶、β-葡萄糖苷酶的活性较CON组显著提高(P<0.05)且高于其他各组。DB组合中外切β-1,4-葡聚糖酶、滤纸酶的活性较CON组显著提高(P<0.05)且高于其他各组。在瘤胃体外发酵试验中,DB组的产气量显著高于CON、HB组(P<0.05)。3个试验组的总挥发性脂肪酸含量显著高于CON组(P<0.05),其中DB组显著高于其他组(P<0.05)。DB组的酸性洗涤纤维体外消化率显著高于CON组(P<0.05),3个试验组的干物质体外消化率、粗蛋白体外消化率、中性洗涤纤维体外消化率均显著高于CON组(P<0.05),且DB组的中性洗涤纤维体外消化率显著高于其他组(P<0.05)。综上,本试验选用的复合菌种发酵均可不同程度提高玉米秸秆中各营养物质消化率和粗纤维降解率,综合分析,以玉米秸秆中接种5%地衣芽孢杆菌+5%黄孢原毛平革菌组合最优。

In this experiment,the corn straw fermented by different compound strains was used as the fermentation substrate,and the rumen in vitro fermentation experiment was carried out to determine the relevant indicators,and the optimal compound strains was selected by combining the indicators.The ex-periment was divided into control group(CON),Aspergillus niger+Bacillus licheniformis group(HD),Ba-cillus licheniformis+Phanerochaete chrysosporium group(DB),Aspergillus niger+Phanerochaete chryso-sporium group(HB).Each treatment group had 3 replicates.After 21 days of sealed fermentation at room temperature,the bag was opened and sampled.The fermentation effect was evaluated by sensory evalua-tion and fermentation index.Meanwhile,the in vi-tro rumen fermentation method was used to deter-mine the gas production parameters,fermentation parameters and in vitro digestibility to evaluate the fermentation effect of different compound strains on corn straw.The results showed that the contents of CF,NDF and ADF in HB group and DB group were significantly lower than those in CON group(P<0.05).The activities of acid xyla-nase andβ-glucosidase in HB combination were significantly higher than those in CON group(P<0.05)and higher than those in other groups.The activity of external sections ofβ-1,4-glucanase and filter paper enzyme in DB combination was significantly higher than that in CON group(P<0.05)and higher than that in other.In the rumen in vitro fermentation test,the gas production of DB group was significantly higher than that of CON and HB group(P<0.05).The TVFA of the three experimental groups was significantly higher than that of the CON group(P<0.05),and the DB group was significantly higher than other groups(P<0.05).The in vitro digestibility of acid detergent fiber in DB group was significantly higher than that in CON group(P<0.05).The in vitro digestibility of dry matter,crude protein and neutral detergent fiber in the three experimental groups was significantly higher than that in CON group(P<0.05),and the in vitro digestibility of neutral detergent fi-ber in DB group was significantly higher than that in other groups(P<0.05).In summary,the fermenta-tion of the composite strains selected in this experiment can improve the digestibility of nutrients and the degradation rate of crude fiber in corn straw to varying degrees.After comprehensive analysis,the combi-nation of 5%Bacillus licheniformis+5%Phanerochaete chrysosporium in corn straw is the best.