莫能菌素浓度对混合瘤胃微生物体外发酵的影响

本试验研究了莫能菌素对混合瘤胃微生物体外发酵的影响 ,以期确定莫能菌素在瘤胃内容物中的适宜添加浓度。混合瘤胃微生物由饲喂花生秧基础日粮的阉公牛瘤胃内容物和瘤胃液制备 ,用简易人工瘤胃装置测定莫能菌素浓度对产气量、瘤胃乙丙酸比例、粗纤维降解率和真蛋白产量的影响。结果表明 ,莫能菌素浓度强烈地抑制产气量 ,两者呈线性负相关(P<0.05);粗纤维降解率开始时随莫能菌素浓度的升高而增加 ,在浓度为0.078mg/L时达到最大值 ,两者呈二次幂函数关系 ;添加莫能菌素降低了瘤胃乙丙酸比例 ,但瘤胃乙丙酸比例随莫能菌素浓度的提高有逐渐增加的趋势 ;在莫能菌素浓度为0.1～2.0mg/L的范围内 ,添加莫能菌素对蛋白质的产量没有明显影响     

Impact of cold-season grazing and supplementary feeding on rumen metabolic parameters and micro-organisms in the ewes of Gansu Alpine Fine Wool Sheep北大核心CSCD

An experiment was conducted to scientifically identify the appropriate feed for Gansu Alpine Fine Wool ewes in order to change the animals' breeding mode, which currently can only be mated at the age of 2.5 years due to insufficient nutritional supply. The experiment selected 48 12-month-old ewes and randomly divided them into group a (Diet 1), group b (Diet 2), group c (Diet 3), and a control group with no supplementary feeding. The feed test was run for 90 days. The rumen pH of groups a and b were very significantly higher (P<0.01) or group c significantly lower (P<0.05) than control group. The rumen ammonia nitrogen, protein nitrogen and total nitrogen of groups a, b and c were all higher than control group (P<0.01). The total volatile fatty acids of group a and b were all higher than the control group (P<0.01), group b significantly higher than group c (P<0.05). The molar ratio of acetic acid and propionic acid in group a was very significantly higher than control group (P<0.01), group b and c were significantly higher than control group (P<0.05). The molar ratio of butyric acid in group a was very significantly higher than group c (P<0.01). The ratio of acetic acid and propionic acid in group b was significantly lower than control group (P<0.05). The number of several rumen fiber-degrading bacteria and protozoa in groups a, b and c were very significantly (P<0.01) or significantly (P<0.05) higher than the control. In conclusion, this study shows that supplementary feeding can positively affect the rumen metabolic parameters and the number of several rumen microorganisms in Gansu Alpine Fine Wool ewes. In general, the effects of Diet 1 were the strongest, while Diet 2 also produced notable improvements. © 2018, Editorial Office of Acta Prataculturae Sinica. All rights reserved.     

速度赛马粪便微生物种群差异的研究

为筛选提高赛马竞技成绩的有益微生物,试验比较现役纯血速度赛马粪便微生物群落多样性及丰度差异.选择休赛一周的现役纯血马9匹,按比赛成绩分为A (16.8 m/s)、B(16.4 m/s)、C(16.3m/s)3组.收集新鲜粪便样本,提取粪便样本菌群DNA,对微生物16S rDNA的V3～V4区序列Illumina测序.结...     

纤维素分解菌ZJW-4产酶条件研究

采用单因素试验法进行不同条件下的液体发酵培养,确定纤维素分解菌ZJW-4的最适产酶条件。结果表明:ZJW-4产纤维素酶的最优发酵条件为以蛋白胨+(NH4)2SO4为氮源的培养基,28℃,pH 6,静置培养48 h。     

碳酸钙和根际作用对酸性红壤解磷微生物丰度的影响

选用玉米品种郑单958为试验材料,设置不添加碳酸钙(CK)、每千克土添加0.3g碳酸钙(Ca-0.3)和0.5g碳酸钙(Ca-0.5)3个碳酸钙处理,以相应处理未种植物土壤为非根际对照土壤,研究了碳酸钙和根际作用对酸性红壤磷酸酶活性及解磷微生物相关功能基因phoC和phoD丰度的影响。结果表明:碳酸钙添加能有效改善玉米生长,促进地上部氮、磷、钾和钙的吸收。土壤酸性磷酸酶(ACP)活性显著高于碱性磷酸酶(ALP)活性,表明酸性土壤中ACP在矿化有机磷方面占主导地位。根际土壤ACP、ALP活性和phoD基因拷贝数均显著高于非根际,而仅Ca-0.5处理ALP活性和phoD基因拷贝数显著高于CK,说明根际效应强于碳酸钙处理。phoC基因拷贝数与土壤铵态氮、硝态氮含量存在显著相关性,ALP活性和phoD基因拷贝数与土壤pH及铵态氮、硝态氮、有效磷、交换性钙含量均存在显著相关性。可见,碳酸钙和根际作用均影响酸性土壤解磷微生物功能和丰度,但根际效应更加明显,这些作用与土壤理化因子的改变密切相关。     

基于宏基因组学的酸性森林土壤氨氧化微生物群落特征研究

全球30％以上陆地面积是酸性土壤(pH<5.5),而酸性土壤中氨氧化微生物群落特征研究是破译其硝化过程微生物学机理的基础.尤其随着完全硝化微生物(Complete ammonia oxidizer,comammox)的发现,亟需重新认知酸性土壤中氨氧化微生物类群.以酸性马尾松林为研究对象,综合利用荧光定量PCR(qPC...     

裙带菜配子体与孢子体的附生微生物群落组成分析

裙带菜(Undaria pinnatifida)是一种重要的大型褐藻,具有较高的经济和食用价值。藻类的附生微生物既能通过代谢产物调控宿主藻类的生长发育,特定条件下又可能导致病害。了解裙带菜附生微生物群落组成对研究裙带菜与附生微生物间的相互作用、种质资源的有效保存以及防治藻类病害等有重要意义。现有研究大多集中于海带和紫菜,关于裙带菜的附生微生物,特别是不同生活史的对比研究还很少。本研究通过16S rRNA基因高通量测序发现,裙带菜配子体和孢子体的附生细菌群落组成有明显差异,配子体样品中的细菌群落丰度和多样性均大于孢子体。配子体中变形菌门(Proteobacteria)(66.67%)为第一优势菌门,其次为拟杆菌门(Bacteroidetes)(13.48%)和蓝细菌门(Cyanobacteria)(11.13%),α-变形菌纲(Alphaproteobacteria)(34.58%)为第一优势菌纲,其次为γ-变形菌纲(Gammaproteobacteria)(31.01%);而孢子体中蓝细菌门(95.67%)占绝对优势,其次为放线菌门(Actinobacteria)(1.65%)和厚壁菌门(Firmicutes)(1.48%)。裙带菜样品经18S rRNA基因测序检测出链形植物(Streptophyta)、纤毛虫门(Intramacronucleata)、担子菌门(Basidiomycota)、顶复亚门(Apicomplexa)、节肢动物门(Arthropoda)、硅藻门(Bacillariophyta)、脊索动物门(Chordata)、腹毛动物门(Gastrotricha)、子囊菌门(Ascomycota)和毛霉菌门(Mucoromycota),其中,担子菌门、子囊菌门和毛霉菌门属于真菌,孢子体的真核微生物群落丰度大于配子体。本研究确定了裙带菜配子体和孢子体附生微生物群落组成以及不同细菌和真核微生物的相对丰度,结果表明,2个世代之间存在显著差异,为后续研究藻类宿主与微生物之间的相互作用、提高海带目褐藻种质保存技术提供了基础的数据支持。     

植物土传病害安全防控技术

概述了几种安全、有效、值得推广应用的植物土传病害的防控技术,包括有益微生物及其代谢产物的利用、蚯蚓粪的利用、太阳能土壤消毒、嫁接技术的应用、微生态调控、生物肥料的使用等,这些方法有望在一定程度上代替化学药剂的使用。     

出口茶叶生产加工中有害微生物危害分析

阐述我国茶叶的对外贸易、茶叶的消费方式等,对各相关的茶叶有害微生物的危害和危害的程度进行了分析,从茶叶的各工艺过程分析茶叶中有害微生物的污染和危害,提出防治茶叶中有害微生物的措施。     

Research Progress on Bacterial Resistance in Environment

Antibiotic resistance genes have become a recognized environmental pollutant, threatening the ecological safety and human health. The application of antibiotics in the clinical and animals breeding, making the environmental microorganisms living with the impact of the residue of antibiotics and elements of resistance genetic and leading to antibiotic resistant bacteria to gain a competitive advantage and destroyed the stability of ecosystem. In this paper, we expounded the concept of resistance gene transmission by the view of macro environment. Through analyzing the mechanism of resistance development,environmental pollution caused by drug resistance and the impact of environmental microorganism for drug resistance, we clarified the key role of the environment in the development of the characteristics of bacterial resistance and analysis environmental resistance.Such as the ecological diversity of flora, the types and the spread of resistant bacteria, the residues of antibiotics and the transmission of the resistance genes.