常温秸秆复合菌系的筛选及其在犊牛生物菌床养殖中的应用

发布时间：2018-01-22 18:26

本文关键词： 复合菌系生物菌床垫料成分饲养密度细菌多样性　出处：《黑龙江八一农垦大学》2017年硕士论文　论文类型：学位论文

【摘要】：近些年我国奶业在快速的发展,规模化奶牛场数量不断增长,随之而来的粪尿污染问题已经成为奶业发展的瓶颈,如何减轻和处理粪污成为奶业发展的热点之一,本研究试图研发一种新型的生物菌床犊牛养殖技术来解决上述问题。采用模拟试验和现场试验结合的方法,对生物菌床的垫料成分和饲养密度进行了选择和优化;筛选出一组在常温条件下能够快速分解木质纤维素的复合菌系,对复合菌系进行细菌多样性分析;以复合菌系为接菌剂接种于生物菌床;运用高通量测序技术分析了垫料中细菌组成多样性,对菌群结构进行了分析。最后提出了犊牛生物菌床养殖技术的主要参数,主要研究结果如下:1、以纤维素降解率为主要指标,富集和筛选得到了一组高效降解纤维素的复合菌系。复合菌系的最适纤维素分解温度为30℃,最适pH值为8.0,此时滤纸和玉米秸秆的降解率分别为66.5%和66.1%,玉米秸秆中的纤维素、半纤维素、木质素的降解率分别为32.0%,85.2%,17.2%。通过高通量测序的技术手段分析了复合菌系的细菌组成多样性,结果表明,在属的水平上,复合菌系主要由假单胞菌属(Pseudomonas sp.)33.9%,拟杆菌属(Bacteroides sp.)11.8%,食酸菌属(Acidovorax sp.)6.9%,产碱杆菌属(Alcaligenes sp.)3.9%,丁酸弧菌属(Butyrivibrio sp.)1.0%等组成。在种的水平上,菌系主要由粪产碱杆菌(Alcallgenes-faecalis)2.0%,空气除氮微枝杆菌(Microvirgula-aerodenitrificans)1.5%等组成。2、饲养密度模拟试验表明,三个模拟密度(T1:头/2m2,T2:头/1.8m2,T3:头1.5/m2)处理间温度差异不显著,模拟饲养密度为T1和T2的氨气排放量较低,在饲养密度上更优先选择这两组进行饲养。在以稻壳和锯末为垫料的模拟试验结果表明,以锯末为垫料效果好,因为锯末处理T1的温度高于其他成分最高温度达到39℃,并且锯末处理T1的氨气排放量低于其他组,最低可达1.456mg/L,因此在垫料成分上优先选择锯末作为垫料的主要成分。3、现场饲养密度试验结果表明,试验设置的三个密度梯度(T1:头/1.6m2,T2:头/1.5m2,T3:头/2m2,对照组CK:头/1.8m2),结果表明,试验过程中T3的表层pH最高,深层pH间没有显著差异,各区域的含水率变化趋势一致,T3的含水率最低,T3的温度也高于其他各组;在第60d时表层最高温度达到32℃,深层温度达到37℃;T3的氨气排放量在45d以前高于其他各组,45d之后氨气排放量低于其他各组,CK的深层氨气排放量远远高于处理组。处理组的总氮含量要高于对照组,总有机碳的含量变化趋向一致,但T3深层的总有机碳高于其他各组,呈现出了一定的优势,因此T3的饲养密度最为适宜。4、对现场试验垫料细菌多样性分析表明,从门的水平上看,变形菌门(Proteobacteria)为优势菌群,各测试点的变形菌门含量均在35%以上,其次是拟杆菌门(Bacteroidetes),除了处理初始阶段,其他各测试点的拟杆菌门含量在27%以上,最高达到41.7%。垫料中属的种类较多,不同处理的不同时间段会出现不同的优势菌属,垫料内部微生物会针对菌群的变化繁殖出可以降解粪便的菌属,像芽孢杆菌属(Paenibacillus sp.)、和梭菌属(Thauera sp.)、纤维弧菌属(Cellvibrio sp.)、假单胞菌属(Pseudomonas sp.)等。通过上述试验,明确了常温秸秆复合菌系的降解能力及细菌组成多样性,并将其运用到了生物菌床中,同时也选择出将锯末作为垫料成分试验效果良好,确定了每头犊牛占地2m2,为生物菌床技术的完善及广泛应用打下了基础。
[Abstract]:In recent years , China ' s dairy industry has been developing rapidly , the number of large - scale dairy cattle has increased , and the problem of manure and urine pollution has become a bottleneck in the development of dairy industry . The results are as follows : 1 . Based on the method of high - throughput sequencing , the composition and density of bacteria are selected and optimized . The results show that the degradation rate of the filter paper and corn stalk is 66.5 % , 85.2 % and 17.2 % respectively . The results showed that the concentration of ammonia in the treated group was higher than that of the other groups . The results showed that the temperature of T3 was higher than that of the other groups . The results showed that the concentration of ammonia in the treated group was higher than that of the other groups . From the level of the door , Protestants were dominant bacteria , and the content of each test point was above 35 % , and the content of bacteroidetes was more than 27 % , and the highest was 41.7 % . In addition to the initial stage , different kinds of bacteria could be found in different time periods . The microorganisms in the bedding could propagate the bacteria belonging to the genus Bacillus , Paenibacillus sp . , Thauera sp . , Cellvibrio sp . , Pseudomonas sp . Through the above tests , the degradation ability and the bacterial composition diversity of the normal - temperature straw composite bacteria system are defined , and the method is applied to the biological bacteria bed , and meanwhile , the test effect of the sawdust as the bedding component is good , the land occupation area of each calf is determined to be 2m2 , and the foundation is laid for the improvement and the wide application of the biological bacteria bed technology .

【学位授予单位】：黑龙江八一农垦大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S823

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