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〔目的〕调查黑龙江省11个边境口岸蜱的种群组成。〔方法〕采用人工小时布旗法采集蜱。〔结果〕在黑龙江省11个边境口岸采获蜱3926只,计3属4种。林缘的优势种群为森林革蜱(95.9%);针阔混交林为全沟硬蜱(46.1%)和森林革蜱(31.8%)。不同口岸的蜱种组成有所不同。绥芬河口岸蜱密度指数最高(93.1%只/人工小时)。不同生境蜱密度指数有所不同。4种蜱的雌雄比:日本血蜱2.7:1,森林革蜱1.7:1,嗜群血蜱1.3:1,全沟硬蜱1.1:1。〔结论〕本次调查为黑龙江省边境口岸地区的蜱种群组成研究提供了依据。 相似文献
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《Vaccine》2018,36(45):6581-6586
INCOGARR is a thematic network recently approved to be financially supported by the Ibero-American Program of Science and Technology for Development (CYTED). The objectives of this Network are the design and evaluation of an efficient and feasible anti-tick vaccine candidate from the technical and economical points of view and also sharing experiences in the immunological control of ticks as part of an Integrated Control Program. The Network consists of seven laboratories and one company from six countries. The first meeting of the Network took place with the representation of each laboratory involved. In the meeting, general and specific objectives and activities of the Network were discussed and it was a very nice example of international collaboration to address an unsolved worldwide topic on tick control in which laboratories with different competencies and expertise join their efforts in a common goal. 相似文献
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Two species of ixodid tick, Ixodes affinis Neumann and Amblyomma maculatum Koch, are simultaneously expanding their ranges throughout the mid-Atlantic region of the US. Although we have some understanding of the ecology and life history of these species, the ecological mechanisms governing where and how new populations establish and persist are unclear. To assess population connectivity and ancestry, we sequenced a fragment of the 16S mitochondrial rRNA gene from a representative sample of individuals of both species from populations throughout the eastern US. We found that despite overlapping host preferences throughout ontogeny, each species exhibited very different genetic and geographic patterns of population establishment and connectivity. I. affinis was of two distinct mitochondrial clades, with a clear geographic break separating northern and southern populations. Both I. affinis populations showed evidence of recent expansion, although the southern population was more genetically diverse, indicating a longer history of establishment. A. maculatum exhibited diverse haplotypes that showed no significant relationship with geographic patterns and little apparent connectivity between sites. Heteroplasmy was also observed in the 16S mitochondrial rRNA gene in 3.5% of A. maculatum individuals. Genetic evidence suggests that these species rely on different key life stages to successfully disperse into novel environments, and that host vagility, habitat stability and habitat connectivity all play critical roles in the establishment of new tick populations. 相似文献
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目的 了解目前长三角城市群蜱媒分布,并对2070年该地区蜱媒适生区进行预测,为该地区蜱媒控制和蜱传疾病防治提供科学依据。方法 检索国内外公开发表的有关长三角城市群蜱媒及病原体分布的文献,提取蜱媒分布地理位置信息,采用刀切法分析最湿季平均温度、最冷季降水量、最干季平均温度、最热月最高温度、最干月降水量、最冷月最低温度、年降水量、平均日间温度范围、降水量季节变化、温度年度范围、温度季节性、年均温度、最暖季平均温度、最湿季降水量、等温性、最冷季平均温度、最湿月降水量、最干季降水量和最暖季降水量等19种气候因子对蜱媒分布的影响。采用最大熵模型分析2020年该地区蜱媒分布,并结合气候因子对2070年蜱媒适生区变化进行预测。结果 共检索中英文文献380篇,累计提取蜱媒分布点148个,并筛选出135个分布点进行研究。长三角城市群存在包括血蜱、扇头蜱、硬蜱、革蜱、牛蜱、璃眼蜱、花蜱在内的7属27种蜱。影响长三角城市群蜱媒分布的气候因子主要为最湿季平均温度和最冷季降水量,其贡献率分别为26.1%和23.6%。2020年,长三角城市群蜱媒高、中、低适生区面积分别为20 337.08、40 017.38、74 931.43 km2。受气候变化影响,2070年蜱媒适生区呈向南部扩大趋势,适生区总面积将增加1.81万km2,高、中、低适生区面积分别扩大至24 317.84、45 283.02、83 766.38 km2。结论 长三角城市群蜱媒种类繁多、分布广泛,未来气候变化可能导致该地区蜱媒分布区域扩大。 相似文献
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Objective To develop the method of 16S rRNA gene clone library for tick bacterial flora analysis, and to analyze the detection effective of pathogens in tick and capacity of bacterial flora diversity. Methods Primers were designed according to the specific gene of Borrelia burgdorferi, Bartonella henselae, Anaplasma phagocytophilum, Ehrlichia chaffeensis and templates were choosen by positive PCR result to amplify the DNA extracted from the ticks. One set of primers targeting 16S rRNA gene conserved region were chosen to amplify certain fragments, DNA extraction, PCR reaction, cloning and sequencing. Nucleotide sequences were compared with GenBank database. Calculated Coverage values of clone library and Shannon-Wiener diversity index. Results Sixteen defined genus-or species-bacteria were detected in 103 valid sequences. Eight species were edge type (Clone No. > 5). Three kinds of pathogens were identified (Borrelia burgdorferi, Bartonella henselae and Rickettsia sp). Three kinds of pathogens were not edge type(Clone No. < 5). Coverage value was 96.11%, and Shannon-Wiener index was 2.40. Analysis results of cloning sequence showed that tick-parasitic bacteria mainly were α and γ deformation mycetes which accounted for 56.25% (9/16). Conclusions The 16S rRNA gene sequences technology could make relative quantitative of bacterial flora, and detect many kinds of pathogens in tick. It's a good method for detection of pathogens and bacterial flora analysis. 相似文献
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Objective To develop the method of 16S rRNA gene clone library for tick bacterial flora analysis, and to analyze the detection effective of pathogens in tick and capacity of bacterial flora diversity. Methods Primers were designed according to the specific gene of Borrelia burgdorferi, Bartonella henselae, Anaplasma phagocytophilum, Ehrlichia chaffeensis and templates were choosen by positive PCR result to amplify the DNA extracted from the ticks. One set of primers targeting 16S rRNA gene conserved region were chosen to amplify certain fragments, DNA extraction, PCR reaction, cloning and sequencing. Nucleotide sequences were compared with GenBank database. Calculated Coverage values of clone library and Shannon-Wiener diversity index. Results Sixteen defined genus-or species-bacteria were detected in 103 valid sequences. Eight species were edge type (Clone No. > 5). Three kinds of pathogens were identified (Borrelia burgdorferi, Bartonella henselae and Rickettsia sp). Three kinds of pathogens were not edge type(Clone No. < 5). Coverage value was 96.11%, and Shannon-Wiener index was 2.40. Analysis results of cloning sequence showed that tick-parasitic bacteria mainly were α and γ deformation mycetes which accounted for 56.25% (9/16). Conclusions The 16S rRNA gene sequences technology could make relative quantitative of bacterial flora, and detect many kinds of pathogens in tick. It's a good method for detection of pathogens and bacterial flora analysis. 相似文献
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蜱是一些人兽共患病的传播媒介和储存宿主,蜱媒传染病是虫媒传染病的重要组成部分。本文就国内外新发蜱媒传染病及其病原体研究热点进行扼要概述。 相似文献
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蜱能传播多种疾病,对畜牧业造成严重损失。现有的蜱杀虫剂和疫苗均存在一定缺陷。本文对蜱杀虫剂,包括化学杀虫剂和非化学杀虫剂(中草药、纳米材料、病毒、真菌、细菌杀虫剂)的研究现状进行综述,分析现有蜱杀虫剂研究中的不足,以期为后续建立更高效、安全的蜱防控方法提供理论参考。 相似文献