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31.
In order to determine the suspected avian cholera pathogen and geneotypes, bacteria isolation technology was used to isolate and culture pathogenic bacteria, the isolated bacteria were identified by traditional methods and molecular biological methods. Geneotyping of the isolated bacteria were determined using PCR technology and gene sequence analysis. The results demonstrated that the isolated bacteria had typical culture characteristics of Pasteurella multocida (Pm),and the morphology of the colony, the characteristics of cell staining, the physiological and biochemical characteristics were consist with Pm; 457 bp fragment was amplified by PCR. Geneotyping results showed that only A primer amplified the target gene fragment of 1 050 bp, sequence analysis also showed that the isolated bacteria shared 97.6% to 100.0% sequence homology with reference strains, and phylogenetic tree analysis showed that the isolated bacteria and A type Pm were in a branch.The experimental results indicated that the isolated bacteria was identified as capsular serotype A of Pm, the results provided reference for the prevention and control of fowl cholera.  相似文献   
32.
对上海地区1个规模化养猪场和1个规模化养鸡场分离鉴定的40株粪肠球菌,采用微量肉汤稀释法对12种抗菌药物进行药敏试验,采用Riboprinter®微生物基因指纹鉴定系统检测分离菌株的基因指纹图谱,分别检测分离菌株中的核糖体型和耐药性。结果表明,在40株粪肠球菌中,80%以上为多重耐药菌株,有4株猪源粪肠球菌对万古霉素耐药,其中有2株表现为对万古霉素高度耐药(MIC>64 mg/L),且对链霉素和庆大霉素同时表现为高度耐药(MIC>2 048 mg/L)。从耐药表型和核糖体分型共同分析粪肠球菌的耐药性,发现多重耐药性严重,同一核糖体型菌株的耐药表型并非完全一致。  相似文献   
33.
【目的】检测中国野生种葡萄以及山欧杂交品种VvmybA1基因型,并对不同材料VvmybA1基因序列进行比对分析,通过对山欧杂种VvmybA1的基因型和表达分析,揭示白色杂交品种‘熊岳白葡萄’果皮无花色苷合成的分子机理。【方法】设计特异性引物,在DNA水平上利用分子克隆手段和绝对荧光定量PCR方法,检测葡萄属的不同样品VvmybA1基因型。采用相对荧光定量PCR手段,对山欧杂交品种果实转色过程中VvmybA1和UFGT的表达量进行分析。【结果】①检测的中国野生种葡萄材料不存在VvmybA1a等位基因;②与欧亚种葡萄相比,中国野生葡萄VvmybA1基因在启动子、内含子以及第三个外显子区域存在不同程度碱基的缺失、插入和替换,表现出丰富的遗传多样性。而且许多野生种葡萄VvmybA1基因的内含子、外显子和启动子区域存在一些特有序列或突变,这些位点可筛选作为鉴别葡萄种和品种的分子标记;③在‘公酿1号’、‘北红’、‘熊岳白葡萄’等山欧杂交葡萄品种以及分类地位未定的‘宿晓红’葡萄中检测到VvmybA1a等位基因,并且‘熊岳白葡萄’为VvmybA1a纯合类型;④RT-PCR分析结果表明,在葡萄果皮转色过程中,‘公酿1号’葡萄果皮VvmybA1和UFGT的表达量增加,然而在‘熊岳白葡萄’果实成熟期未检测到VvmybA1和UFGT 的表达。【结论】证明VvmybA1a等位基因是欧亚种葡萄以及其杂交种独有的基因型,不存在于中国野生种葡萄中,推测‘宿晓红’葡萄具有欧亚种葡萄血缘;葡萄属不同种的VvmybA1基因序列比对分析揭示,山欧杂交品种‘熊岳白葡萄’果皮不能合成花色苷是由于VvmybA1a纯合,VvmybA1不表达。  相似文献   
34.
Late blight, caused by the oomycete Phytophthora infestans, is considered the most important and destructive disease of potato in Turkey. In this study, characterization of 367 isolates of P. infestans obtained from the potato-growing areas of the country was carried out to evaluate the pathogen population structure over the 2017–2019 production seasons. The isolates were characterized by numerous features including mating type, in vitro mefenoxam sensitivity, simple-sequence repeat (SSR) markers, and virulence against a set of potato differential lines. Most isolates were A2 mating type (353 isolates). Also, 68% of isolates were resistant to mefenoxam; the remainder were intermediate in their sensitivity and there were no sensitive isolates. SSR-based genotypic analysis of P. infestans populations showed a low genetic diversity. The 13_A2 clonal lineage predominated with a frequency of 92.1%, followed by 34_A1 (3.3%) and 37_A2 (2.7%). Genotypes 34_A1 and 37_A2 were detected only in 2019. This is the first report of 34_A1 and 37_A2 clonal lineages causing late blight disease of potato in Turkey. The most abundant virulence type was one overcoming resistance genes R1, R2, R3, R4, R6, R7, R10, and R11. These results emphasized that the migration of individuals and the asexual generation of subclonal differences were the main factors driving the population structure of P. infestans in Turkey.  相似文献   
35.
试验旨在探究SPP1基因g.36651870T>C位点多态性、PLCB3基因g.41871219T>C位点多态性与绵羊产羔数之间的关系,以期寻找绵羊产羔数性状相关的分子标记.利用全基因组重测序结合Sequenom MassARRAY?SNP技术对多羔羊(小尾寒羊、湖羊、策勒黑羊)和单羔羊(滩羊、苏尼特羊、萨福克羊和草原...  相似文献   
36.
37.
This study was to investigate the ribosome genotyping and antimicrobial resistance in Enterococcus faecalis strains isolated from 2 large-scale farms in Shanghai.40 isolates were evaluated for their sensitivity to 12 antimicrobial agents by broth microdilution,and the ribosome genotyping (ribotype) was characterized by the Riboprinter® Microbial Characterization System.The resistance rates of most antimicrobial drug were relatively high and multidrug resistant strains were detected with more than 80%.4 strains of Enterococcus faecalis isolated from pigs were resistant to vancomycin,including 2 strains of vancomycin highly resistant (MIC>64 mg/L) with the same time highly resistant to gentamicin and streptomycin (MIC>2 048 mg/L).The results showed that multidrug resistance of Enterococcus faecalis was a serious issue,and the resistant phenotypes of the same type of ribotype was not entirely consistent.  相似文献   
38.
To understand the Salmonella epidemic characteristics and pulsed field gel electrophoresis(PFGE)genotyping of goose,Anserindicus and Cygnus,33 strains of Salmonella were serotype typed by PFGE and genotyped with BioNumerics 6.6 cluster analysis software.The results showed that there were 16 PFGE patterns,which displayed 6 strains Salmonella paratyphi C,19 strains Salmonella thompson,1 strains Salmonella paratyphi B,1 strain Salmonella irumu,1 strain Salmonella oslo,5 undifferentiated.PFGE similarity is about 53.7% to 100.0%,and most of the strains and anthropogenic strains similarity was more than 80%.The results showed that goose,Anserindicus and Cygnus Salmonella serotypes same PFGE type with a high degree of similarity,and possibly from the same clone,quite different serotypes PFGE band pattern difference.  相似文献   
39.
为研究KISS1基因在常年发情的小尾寒羊和季节性发情的草地型藏羊中的表达模式,以及KISS1基因多态性与绵羊繁殖之间的关系,实验采用qPCR技术对比分析KISS1基因在2个品种绵羊的10种繁殖相关组织中的表达差异,同时利用Sequenom MassARRAY~?SNP技术对常年发情绵羊(小尾寒羊、策勒黑羊和湖羊)和季节性发情绵羊(滩羊、苏尼特羊和草地型藏羊)KISS1基因2个SNPs位点多态性进行检测,并与小尾寒羊产羔数进行关联分析。qPCR结果显示:KISS1基因在小尾寒羊下丘脑、大脑、垂体和甲状腺中的表达量高于草原型藏羊(P<0.05);分型结果表明,g.1317523C>T位点基因型频率和等位基因频率在常年发情和季节性发情绵羊品种间差异均达到极显著水平(P<0.01);群体遗传学分析表明,g.1317523C>T位点在6个绵羊群体中均表现为中度多态(0.25T位点在小尾寒羊、滩羊、苏尼特羊和湖羊中均处于哈代温伯格平衡状态(P>0.05),g.1311578G>T位点在苏尼特羊和湖羊中处于哈代温伯格平衡状态(P>0.05);关联分析表明,这2个SNPs位点与小尾寒羊前3胎产羔数均无显著关联(P>0.05),但g.1311578G>T位点TT型各胎产羔数均大于GT和GG型。综上,KISS1基因与绵羊的季节性繁殖密切相关,并且g.1311578G>T位点对绵羊产羔性状有潜在调控作用。  相似文献   
40.
We investigated the effects of different strategies for genotyping populations on variance components and heritabilities estimated with an animal model under restricted maximum likelihood (REML), genomic REML (GREML), and single‐step GREML (ssGREML). A population with 10 generations was simulated. Animals from the last one, two or three generations were genotyped with 45,116 SNP evenly distributed on 27 chromosomes. Animals to be genotyped were chosen randomly or based on EBV. Each scenario was replicated five times. A single trait was simulated with three heritability levels (low, moderate, high). Phenotypes were simulated for only females to mimic dairy sheep and also for both sexes to mimic meat sheep. Variance component estimates from genomic data and phenotypes for one or two generations were more biased than from three generations. Estimates in the scenario without selection were the most accurate across heritability levels and methods. When selection was present in the simulations, the best option was to use genotypes of randomly selected animals. For selective genotyping, heritabilities from GREML were more biased compared to those estimated by ssGREML, because ssGREML was less affected by selective or limited genotyping.  相似文献   
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