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1.
In Latin and Central America and in most Asian countries, brucellosis remains an insufficiently studied disease. This study aims to determine the national and regional incidence of brucellosis among cattle (cows) and small ruminants (sheep, goats) in the Republic of Kazakhstan, as well as to identify the effect of climatic and geographical factors on the incidence rates. Thematic maps were created in an open geographic information system QGIS version 2.8. in order to identify the natural and socio-economic factors that influence the spread of the disease overlay method was used. Local cluster analysis was used in order to identify additional causes of the disease. Findings show the following values of Pearson correlation between the overall population and the number of animals infected: 0.68 for cows, p ≤ 0.005, and 0.56 for sheep and goats, p ≤ 0.03. Thus, the larger the heard in a given area, the greater likelihood of having brucellosis. Data processing reveals that Kazakhstan has almost twice as many regions good for cattle breeding as regions that are good for the small ruminants farming. The correlation variables for cattle and small ruminants are approximately the same. On the basis of the performed research the author proposes to amend the accepted methodology of epidemiology surveillance by the methods based on spatial (geographical) analysis. It is also proposed to adjust the process of breeding cattle and small ruminants considering the additional health recommendations that take into account the geographical aspects of the spread of the disease.  相似文献   
2.
Natural killer (NK) cells play a role in innate antiviral immunity by directly lysing virus-infected cells and producing antiviral cytokines such as interferon gamma (IFN-γ). We developed a system for characterizing the bovine NK response to foot-and-mouth disease virus (FMDV), which causes a disease of cloven-hoofed animals and remains a threat to livestock industries throughout the world. IL-2 stimulation of PBMC resulted in poor killing of human K562 cells, which are often used as NK target cells, while lysis of the bovine BL3.1 cell line was readily detected. Depletion of NKp46-expressing cells revealed that 80% of the killing induced by IL-2 could be attributed to NKp46+ cells. In order to characterize the response of NK cells against FMDV in vivo, we infected groups of cattle with three different strains of the virus (A24 Cruzeiro, O1 Manisa, O Hong Kong) and evaluated the cytolytic ability of NK cells through the course of infection. We consistently observed a transient increase in cytolysis, although there was variation in magnitude and kinetics. This increase in cytolysis remained when CD3+ cells were removed from the preparation of lymphocytes, indicating that cytolysis was independent of MHC-T cell receptor interaction or γδ T cell activation. In contrast, animals monitored following vaccination against FMDV did not exhibit any increase in NK killing. These data suggest that NK cells play a role in the host immune response of cattle against FMDV, and contrast with the suppression of NK activity previously observed in swine infected with FMDV.  相似文献   
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为确诊贵州省都匀市某养殖场的猪死亡病因,采集病死猪病料进行猪繁殖与呼吸综合征病毒、猪瘟病毒、猪伪狂犬病病毒、猪圆环病毒2型核酸检测,细菌分离鉴定及药物敏感试验。结果:猪繁殖与呼吸综合征病毒实时荧光定量RT-PCR检测和猪圆环病毒2型PCR检测核酸均为阳性,其余病毒核酸检测均为阴性。细菌分离培养表明存在细菌感染,分子生物学鉴定为奇异变形杆菌;分离菌对硫酸安普霉素、硫酸粘菌素、盐酸大观霉素+盐酸林可霉素、氟苯尼考较敏感,对多种药物产生耐药。结论:确诊病例为猪繁殖与呼吸综合征病毒、猪圆环病毒2型、奇异变形杆菌混合感染。  相似文献   
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弓形虫可感染多种动物引起严重的弓形虫病,为了对不同宿主感染的弓形虫株基因型差异及不同基因型弓形虫虫株的致病力差异进行进一步研究,弓形虫基因型的分析多采用限制性片段长度多态性PCR(PCR-RFLP)、随机扩增多态性DNA、多位点PCR-RFLP分析、DNA序列分析和微卫星DNA序列分析等技术,扩增位点多选择SAG1、SAG2、SAG3、BTUB和GRA6等遗传标记。传统的弓形虫基因型主要有3个,随着基因型研究的不断深入,越来越多的基因型被发现。本文就弓形虫基因分型研究进展进行讨论分析。  相似文献   
7.
Differences in virulence between Fusarium sulphureum and Fusarium sambucinum were compared. Changes in reactive oxygen species production and metabolism in inoculated slices of potato tubers were also compared. The result showed that Fusarium infection induced significant production of ROS, lipid peroxidation and loss of cell membrane integrity, but low activity of superoxide dismutase (SOD) and ascorbate peroxidase (APX). Compared to F. sambucinum, F. sulphureum led larger lesion diameters on potato tubers and slices. It resulted in more superoxide anion (O2-) and earlier peak of hydrogen peroxide (H2O2), but lower activity of catalase (CAT) and APX, and accompanied with higher malondialdehyde (MDA) content and lower cell membrane integrity. These findings suggested that overproduction of ROS involved in the pathogenicity of Fusarium in potato tubers.  相似文献   
8.
        黄曲霉毒素污染是影响花生食用安全性和制约产业发展的重要因素。荚壳是花生抵御黄曲霉菌侵染的第一道防线,为建立花生荚壳抗黄曲霉侵染的鉴定方法,本研究利用强侵染黄曲霉菌AF2202接种花生荚果,通过对不同接种菌浓度和培养时间的比较分析,发现接种浓度为2 ×106孢子/mL、培养7d的组合方案可以有效区分花生荚壳对黄曲霉菌侵染的抗性。利用所建立的鉴定方法对276份遗传变异丰富的花生核心种质材料进行接种鉴定,进一步证明了这一方法鉴定花生荚壳抗性的有效性和实用性,初步发掘出2份具有荚壳抗性的特异花生种质。  相似文献   
9.
农杆菌介导小麦遗传转化影响因素的研究   总被引:1,自引:0,他引:1  
选用河南科技学院近年来选育的小麦品种百农160的成熟胚愈伤组织和农杆菌菌株LBA4404,对农杆菌介导遗传转化中农杆菌浓度、感染时间、乙酰丁香酮浓度、头孢霉素质量浓度等几个重要影响因素进行了研究,建立小麦高效转化体系.结果表明.菌液OD<,600>=0.6,侵染时间30min时对愈伤组织的生存和转化最有利;浓度为200...  相似文献   
10.
茄链格孢菌侵染马铃薯叶片过程的细胞学观察   总被引:2,自引:0,他引:2  
采用光学显微镜和电镜技术系统研究了茄链格孢菌对马铃薯叶片的侵染过程及超微结构特征。结果表明:接种2 h后,分生孢子开始萌发,分生孢子各个位置都可萌发产生芽管|接种6 h后,菌丝顶端出现附着孢|接种8 h后,菌丝从细胞间凹陷处直接侵入感病品种东农303叶片表皮细胞内|接种24 h后,受侵染寄主细胞中的菌丝向相邻细胞扩展蔓延,感病品种细胞内含物及各类细胞器基本完全消解。在抗病品种克新1号上,茄链格孢菌的侵染情况与感病品种基本一致,但发生时间明显较感病品种推迟,寄主细胞内的菌丝数量明显少于感病品种|并且在接种24 h后出现细胞壁加厚的防卫反应,在感病品种上没有观察到防卫反应现象。说明抗病品种对茄链格孢菌具有一定的抗侵入和抗扩展能力。  相似文献   
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