我国东北地区蓝舌病传播媒介尖喙库蠓生态地理分布与基于分子遗传学的迁移研究

Bluetongue is listed as the Class-A animal disease by the Ministry of Agriculture in China, of which Culicoides serve as the propagation medium, and there is a risk of introduction of bluetongue in the northeast of China. During the participation in the national key research and development projects, we found that the distribution of detected serological positive animals of blue tongue virus in our country was influenced by climate and geographical conditions, and as the medium of bluetongue virus, Culicoides oxystoma distributed in the northeast region and other areas where such virus was detected. In this research, we firstly took the samples of Culicoides oxystoma through field investigation, and drew the electronic map of spatial distribution of Culicoides oxystoma; secondly, we analyzed the effect of meteorological and geographic conditions in northeast China on the distribution of Culicoides oxystoma by using niche model, and evaluated and predicted the potential natural epidemic foci of bluetongue in this region; finally, we used PCR and other molecular biological techniques for the acquisition of mitochondrial DNA of Culicoides oxystoma, analyzed its sequential evolution characteristics based on phylogenetic geography, further determined the origin and migratory route of Culicoides oxystoma in northeast China, and assessed and predicted the possible introduction and propagation paths of bluetongue in this region. The research results can not only provide a scientific basis for developing the bluetongue prevention and control plan in northeast China, and improving the level of regional healthy farming level, but also provide valuable scientific data for the prevention and control of bluetongue and other Culicoides-borne diseases in other areas of China as well as the research & development of anti-Culicoides drugs.

蓝舌病是我国农业部规定的动物一类疫病，库蠓是其传播媒介，我国东北地区面临蓝舌病传入的风险。申请人前期研究发现我国已检出的蓝舌病毒血清学阳性动物样本的分布受气候、地理条件的影响，而尖喙库蠓作为蓝舌病毒传播媒介在东北地区和已检出该病毒的地区都有分布。本研究首先通过现场调查采集尖喙库蠓样本，绘制东北地区尖喙库蠓空间分布电子地图；其次，利用生态位模型，分析东北地区气象、地理条件对尖喙库蠓分布的影响，评估预测蓝舌病在该地区的潜在流行区域；最后，利用PCR等分子生物学技术采集尖喙库蠓线粒体DNA，利用系统发育地理学方法分析其序列进化特征，进一步判断东北地区尖喙库蠓的发源地及迁移路线，评估预测该地区蓝舌病可能的传入、传播路径。研究的结果可为制定蓝舌病防治规划，提高区域养殖健康水平提供科学依据，也可为我国其它地区蓝舌病等库蠓传播疾病的防控及抗蠓药物的研制提供有价值的科学资料。

蓝舌病是我国农业部规定的动物一类疫病，库蠓是其传播媒介，我国东北地区面临蓝舌病传入的风险。申请人前期研究发现我国已检出的蓝舌病毒血清学阳性动物样本的分布受气候、地理条件的影响，而尖喙库蠓作为蓝舌病毒传播媒介在东北地区和已检出该病毒的地区都有分布。本研究首先通过现场调查采集尖喙库蠓样本，绘制东北地区尖喙库蠓空间分布电子地图；其次，利用生态位模型，分析东北地区气象、地理条件对尖喙库蠓分布的影响，评估预测蓝舌病在该地区的潜在流行区域；最后，利用PCR等分子生物学技术采集尖喙库蠓线粒体DNA，利用系统发育地理学方法分析其序列进化特征，进一步判断东北地区尖喙库蠓的发源地及迁移路线，评估预测该地区蓝舌病可能的传入、传播路径。.研究结果显示：通过空间自相关技术分析发现，尖喙库蠓在我国的分布不具有空间自相关性。通过质心分布转移技术分析发现，尖喙库蠓适生区质心在RCP4.5和RCP8.5气候情景下则均向北移动。通过构建MaxEnt模型显示，最冷月份最高温、最干月份降雨量和牧场面积是影响尖喙库蠓在我国分布的重要环境因素。尖喙库蠓当前潜在高度适生区主要分布在四川、重庆、湖北、安徽。预测2030年和2050年气候变暖情景下库蠓的环境适应性发现，尖喙库蠓将在内蒙、辽宁、新疆和甘肃建立新的环境适宜区。系统发育学分析发现，我国东北地区采集到的尖喙库蠓样本与日本等地的尖喙库蠓存在较近亲缘关系。这些成果的获得为研究我国尖喙库蠓分布与迁徙规律提供了参考，也为制定蓝舌病防治规划，预警新发库蠓传播动物疾病，提高养殖健康水平及研制抗蠓药物提供有价值的科学资料。