生物添加剂对羊草青贮饲料超微结构和纤维变化的影响  

Effect of biological additives on ultrastructure and fiber content of Leymus chinensis silage

作　　者：杨红[1] 张庆[1] 侯建建[1] 玉柱[1] 

机构地区：[1]中国农业大学动物科技学院,北京100193

出　　处：《草业学报》2016年第12期94-101,共8页Acta Prataculturae Sinica

基　　金：国家牧草产业技术体系(CARS-35);公益性行业(农业)科研专项经费项目(201303061);天津市农业科技成果转化与推广项目(201404040);内蒙古自治区科技计划项目(苜蓿混合青贮调制技术研究与示范)资助

摘　　要：本试验旨在研究纤维素酶和乳酸菌的单独和复合添加对羊草青贮饲料超微结构和纤维组分的影响。将1060U/g的纤维素酶(CEL)、1×105 CFU/g的干酪乳杆菌(LC)、1060U/g的纤维素酶和1×105 CFU/g的干酪乳杆菌复合添加剂(LC+CEL)添加到羊草中经过切短后装入0.5L青贮桶中制作青贮饲料,每个处理3个重复。在常温状态下贮存45d,测定发酵品质和营养品质变化并用透射电镜观察其超微结构。结果表明,混合组LC+CEL的pH为3.86显著低于LC和CEL处理组(P<0.05),乳酸和乙酸含量显著高于LC和CEL处理组(P<0.05)。与对照组相比,LC+CEL处理组显著降低43.9g/kg的中性洗涤纤维、22.3g/kg的酸性洗涤纤维、28.5g/kg的纤维素和21.6g/kg的半纤维素,增加20.5g/kg的可溶性碳水化合物,29.2g/kg乳酸。3个添加剂处理组中性洗涤纤维和酸性洗涤纤维含量均显著低于对照组(P<0.05),可溶性糖和有机酸含量显著高于对照组(P<0.05)。总之,添加生物添加剂能破坏羊草的细胞结构,提供可溶性碳水化合物作为发酵底物,快速降低pH促进厌氧发酵。复合添加干酪乳酸菌和纤维素酶降解细胞壁和细胞内容物,将其转化为可溶性糖和有机酸的效果最好,单独添加干酪乳酸菌和单独添加纤维素酶的效果次之。生物添加剂对羊草叶片不同部位和结构的细胞降解程度不同,羊草薄壁组织容易降解,木质化程度越高的厚壁细胞降解越困难。The aim of this study was to determine the effects of adding the cellulose（CEL）and Lactobacillus casei（LC）separately or together on the quality of Leymus chinensis silage.Chopped L.chinensis was supplemented with 1060 U/g cellulose,1×10^5 CFU/g fresh matter L.casei,or both（LC＋CEL）.Chopped L.chinensis with no additives served as the control.Three replicates of each treatment were weighed and chopped into 0.5Lplastic buckets,and these mini silos were stored at ambient temperature for 45 days.The ultrastructure of stems,fermentation quality,and nutrient composition of the L.chinensis silage were analyzed.The pH in the LC＋CEL mixture was 3.86,which was significantly lower than those in the LC and the CEL treatments（P〈0.05）,but the lactic acid and acetic acid contents in the LC＋CEL mixture were significantly higher than those in the LC and the CEL treatments（P〈0.05）.The LC＋CEL mixture showed significantly decreased neutral detergent fiber（43.9g/kg）,acid detergent fiber（22.3g/kg）,cellulose（28.5g/kg）,and hemicellulose（21.6g/kg）contents,and increased water soluble carbohydrates（20.5g/kg）and lactic acid（29.2g/kg）contents after 45 days of fermentation.Compared with the control（no additives）,all of the treatments showed significantly lower neutral detergent fiber and acid detergent fiber contents,and significantly higher water soluble carbohydrates and organic acids contents（P〈0.05）.Overall,the LC＋CEL mixture performed better in terms of degrading fiber to water soluble carbohydrates and organic acids than did either LC or CEL,but all of the treatments performed better than the control.The biological additives degraded the different tissues to varying degrees,with greater degradation of parenchyma tissue and less degradation of lignified tissue.

关 键 词：羊草 细胞壁 生物添加剂 超微结构 纤维 

分 类 号：S816.53[农业科学—饲料科学]