菌群组合效应对玉米秸秆微贮饲料发酵品质及营养价值的影响

Effects of Microbial Combination on Fermentation Quality and Nutritional Level of Corn Straw Micro-Storage Feed

为研究菌群组合效应对玉米秸秆微贮饲料发酵品质的影响,试验分为4组:A组(玉米秸秆),B组(玉米秸秆+0.5%裂褶菌),C组(玉米秸秆+0.5%裂褶菌,乳酸杆菌和酵母菌复合物),D组(玉米秸秆+0.25%裂褶菌密闭发酵7 d+0.25%乳酸菌和酵母菌复合物密闭发酵21 d),试验A组、试验B组和试验C组均密闭发酵28 d。分别在发酵第7,14,21和28天开袋取样,用于常规化学成分分析及消化率测定。结果表明:试验期7 d,试验C组pH显著低于另3组(P<0.05)。14~28 d,试验C组与试验D组样品的pH显著低于另2试验组(P<0.05)。试验期14~28 d,试验C组与试验D组样品粗蛋白(CP)水平显著上升(P<0.05);试验期0~28 d,各组纤维含量均呈下降趋势。试验期21 d,试验D组粗纤维(CF)含量显著低于其他3组(P<0.05);与试验A组相比,添加菌群密闭发酵均能显著提高微贮玉米秸秆的体外消化率(P<0.05)。裂褶菌与益生菌能有效降低玉米秸秆微贮饲料中的粗纤维并提高微贮秸秆的营养价值,分段使用裂褶菌和乳酸菌与酵母菌的组合密闭发酵效果最好。

This study was aimed to investigate the effects of microbial combination on fermentation quality of corn straw micro-storage feed.According to different compound microbial supplements,4treatments were designed(with 6 replicates in each group and 1 ferment bag of diet per replicate):Control group was corn straw,Group 1 was corn straw with 0.5%Schizophyllum supplement,Group 2was corn straw with 0.5%compound microbial supplement(Schizophyllum,Lactic acid bacteria and yeast),Group 3 was corn straw with 0.25%Schizophyllum closed fermentation for 7 d and 0.25%Lactic acid bacteria and yeast closed fermentation for 21 d.Control group,group 1 and Group 2 were fermented under closed conditions for 28 d.Samples obtained at 0,7,14,21 and 28 d.Mycotoxins,pH,aerobic stability,nutrient content and in vitro digestibility were determined and analyzed.On the 7 d of the test period,pH of group 2 was significantly lower than that of other groups(P<0.05).During14~28 d,pH of group 2 and group 3 was significantly lower than that of other two groups(P<0.05).The crude protein(CP)level of straw in group 2 and group 3 increased significantly(P<0.05)during the test period from 14 to 28 d.The fiber content of all groups showed a downward trend from 0 to28 d.On the 21 d,CF content of straw in group 3 was significantly lower than that in other three groups(P<0.05).Compared with the control group,the closed fermentation of the added bacteria could significantly increase in vitro digestibility of corn straw micro-storage feed(P<0.05).In summary,Schizophyllum and probiotics can effectively reduce the crude fiber in corn straw micro-storage feed and improve the nutritional value of micro-storage corn straw.Schizophyllum,Lactic acid bacteria and yeast supplied in different periods can achieve the best result.