瘤胃源牛链球菌提高紫花苜蓿的青贮品质

Streptococcus Equinus Isolated from The Rumen of Dairy Cows Improved The Silage Quality of Alfalfa

试验为检测从荷斯坦奶牛瘤胃中分离的三株牛链球菌(Streptococcus equinus,S.equinus)对苜蓿青贮品质的影响,将植物乳杆菌(Lactobacillus plantarum,L.plantarum)FE-1(CB组)、牛链球菌ON182139(S1组)、ON182142(S2组)、ON221850(S3组)等乳酸菌用于新鲜苜蓿青贮,以不额外接种乳酸菌作为对照组(CON),在青贮的3、6、12、30 d和60 d,分别取出青贮苜蓿,测定化学成分、发酵品质、微生物数量和有氧稳定性。结果表明:①第60天,与CON组相比,各添加乳酸菌组均显著降低了干物质损失(P<0.05),但牛链球菌组与植物乳杆菌组之间差异不显著(P>0.05)。②与CON组相比,相同添加量的乳酸菌组苜蓿的酸性洗涤纤维(ADF)、pH、氨态氮(NH3-N)和好氧菌群显著降低(P<0.05),但牛链球菌组和植物乳杆菌组之间差异不显著(P>0.05)。③对于粗蛋白(CP),与CON组相比,S3组与CB组显著降低了CP损失(P<0.05),但牛链球菌组与植物乳杆菌组组之间差异不显著(P>0.05)。④S3组乳酸(LA)和乙酸(AA)均显著升高(P<0.05),且与CB组差异显著(P<0.05)。牛链球菌的添加对提高苜蓿青贮品质有一定的积极作用,牛链球菌可以应用于苜蓿青贮中。

The objective of this study was to examine the effects of three strains of Streptococcus equinus(S.equinus)isolated from the rumen of Chinese Holstein dairy cows on the quality of alfalfa silage.The fresh alfalfa were silaged with each of the following lactic acid bacteria:Lactobacillus plantarum(L.plantarum)FE-1 group(CB),S.equinus ON182139(S1),ON182142(S2),ON221850(S3).No extra inoculate was set as control group(CON).On the 3rd,6th,12th,30th and 60th days of silage,the alfalfa was used for determination of the chemical composition,fermentation quality,microbial quantity and aerobic stability.The results showed that:①on 60th day,all groups added with lactic acid bacteria significantly reduced dry matter loss compared to the CON group(P<0.05),but the difference between the S.equinus group and the L.plantarum group was not significant(P>0.05).②Compared with the CON group,the ADF,pH,NH3-N,and aerobic bacteria of alfalfa significantly decreased in the same addition of lactic acid bacteria group(P<0.05),but the difference between the S.equinus groups and L.plantarum group was also not significant(P>0.05).③For CP,compared with the control group,the S3 group and CB group significantly reduced its losses(P<0.05),but the difference between the L.plantarum group and S.equinus groups was not significant(P>0.05).④For both lactic acid(LA)and acetic acid(AA),the S3 group significantly increased its concentration(P<0.05),and the difference was significant compared with the CB group(P<0.05).The addition of S.equinus had a certain positive effect on improving the quality of alfalfa silage,and the application of S.equinus in silage is recommended.