土壤污染及乳酸菌添加对紫花苜蓿青贮品质的影响  

Effect of Soil Contamination and Lactic Acid Bacteria Inoculation on Alfalfa Silage Quality

作　　者：孙娟娟[1] 赵金梅[1] 薛艳林 刘洪林[1] 李薇[1] 玉柱[3] 白春生[4] SUN Juan-juan;ZHAO Jin-mei;XUE Yan-lin;LIU Hong-lin;LI Wei;YU Zhu;BAI Chun-sheng(Institute of Grassland Research of Chinese Academy of Agricultural Sciences,Hohhot 010010,China;Inner Mongolia Academy of Agricultural and Animal Husbandry Sciences,Hohhot 010031,China;College of Grassland Science and Technology,China Agricultural University,Beijing 100193,China;Shenyang Agricultural University,Shenyang 110866,China)

机构地区：[1]中国农业科学院草原研究所,内蒙古呼和浩特010010 [2]内蒙古自治区农牧业科学院,内蒙古呼和浩特010031 [3]中国农业大学草业科学与技术学院,北京100193 [4]沈阳农业大学,辽宁沈阳110866

出　　处：《中国草地学报》2021年第8期114-120,共7页Chinese Journal of Grassland

基　　金：公益性(农业)行业科研专项(201303061);内蒙古自然科学基金(2018MS03028);国家自然科学基金(31302029);国家重点研发计划项目(2017YFD0502106-3)。

摘　　要：以不添加土壤和乳酸菌为对照,设土壤添加、乳酸菌添加及土壤与乳酸菌混合添加处理,在室温罐贮条件下测定贮藏第7d、14d、28d和49d的pH值、发霉率以及贮藏49d青贮微生物数量、营养成分和发酵品质,分析土壤污染和乳酸菌添加对紫花苜蓿青贮的影响。结果表明,土壤添加处理苜蓿青贮饲料的pH值和发霉率从青贮14d开始显著高于对照(P<0.05),青贮49d时大肠杆菌数是对照的10倍以上(P<0.05),粗蛋白含量比对照降低了10.6%(P<0.05),灰分含量比对照增加了62.9%(P<0.05);土壤与乳酸菌混合添加青贮14d时的pH值显著低于对照和土壤添加处理(P<0.05),青贮28d才有少量的发霉现象,中性洗涤纤维和酸性洗涤纤维含量显著降低(P<0.05),霉菌与酵母菌数量约为对照的1/10(P<0.05),大肠杆菌数量约为对照的1/100(P<0.05);表明土壤污染导致紫花苜蓿青贮饲料发霉率增加,发酵品质和粗蛋白含量降低,增加了灰分含量,而乳酸菌添加能够有效抑制被土壤污染的苜蓿青贮饲料的不良微生物数量,降低发霉率,减少了土壤污染对苜蓿青贮造成的损失。The study was conducted to determine the effect of soil contamination and lactic acid bacteria(LAB)on fermentation quality and chemical composition of alfalfa silage.Four treatments were set up,including control treatment without adding soil and LAB,soil addition treatments,LAB addition treatment and mixed addition treatment of soil and LAB.Under the condition of canned jar storage at room temperature,the pH and moldy rate were measured at 7d,14d,28d and 49d,as well as the number of microorganisms,nutrient components and fermentation quality at 49d were measured.The results showed that the pH value and moldy rate of alfalfa silage treated with soil addition were significantly higher than those of the control from 14 days after ensiling.The number of Escherichia coli at 49 days after ensiling was more than 10 times higher than that of the control(P<0.05),the crude protein content was 10.6%lower and the ash content was 62.9%higher than that of the control(P<0.05).The pH value of alfalfa silage treated with mixed addition of soil and LAB was significantly lower than that of the control and soil treatment after 14 days of silage fermentation(P<0.05),and there was a small amount of mildew after 28 days,at the same time,the content of neutral detergent fiber(NDF)and acid detergent fiber(ADF)were significantly reduced(P<0.05).The number of mold and yeast was about 1/10 of the control(P<0.05),and the number of Escherichia coli was about 1/100 of the control(P<0.05).In conclusion,soil contamination increased the moldy rate of alfalfa silage,reduced the fermentation quality and crude protein content,and increased the ash content.The addition of LAB can effectively inhibit the growth of undesirable microorganisms in alfalfa silage contaminated by soil,reduce the moldy rate of silage,and alleviate the loss of alfalfa silage caused by soil contamination.

关 键 词：土壤污染 紫花苜蓿 乳酸菌添加剂 发霉率 微生物数量 

分 类 号：S816.53[农业科学—饲料科学]