Culex Quinquefasciatus。资料来源：维基百科

The host animals from which a female mosquito takes her blood meal influences the pathogens she can be exposed to and, by extension, the potential role her species may have as a vector of disease. In this post, I outline my recent research investigating the vertebrate species fed on by mosquitoes in the United Kingdom.

英国播放了大约34种蚊子，有潜在的卵35^Th，，，，The invasive艾德（Aedes botictus），在后期被发现2016。Although no mosquito-borne pathogens of veterinary or human importance are currently thought to circulate in the UK, several species are known vectors of pathogens including importantvirusesandmalaria。此外，已知许多物种会引起相当大的咬伤给人类。

但是，我们对本地蚊子的喂养行为的理解是相当有限的，尤其是关于鸟类被喂养的。

Farms as environments for mosquitoes

作为我的博士工作的一部分，我专注于了解牲畜农场上的蚊子主持人互动。农场是有趣的研究地点，因为它们是各种野生和家庭哺乳动物（加人类）的所在地，并为包括蚊子在内的多种昆虫提供了自然和人造的结构和栖息地。我的研究最近出版了Parasites and Vectors，，，，posed the question: which animals are farm-associated mosquitoes feeding on? I elected to find the answer at a coastal grazing marsh on the Isle of Sheppey in Kent, an area long associated with high mosquito densities and historical vivax malaria transmission.

Collecting blood-fed mosquitoes

到目前为止最具挑战性的方面blood-fed mosquitoes is collecting suitable numbers of them from the field. After blood-feeding, females will find an area where they can safely rest and digest their meal. This process takes several days depending on the species, volume of blood consumed and the environmental conditions. Blood-fed individuals are poorly attracted to the most commonly-used mosquito traps which use light and/or host-derived scents as bait.

考虑到这一点，我将建筑物，鸡舍和休息盒的愿望转向了我的主要收集方法。我的休息盒是光荣的包装箱，为蚊子提供了庇护所，可以从那里吸出它们。

回到实验室后，将蚊子粉碎成溶液，提取DNA和针对线粒体基因细胞色素的PCR测序方法C氧化酶我用来识别血液粉的起源。

The collections yielded over 20,000 mosquitoes of 11 species (although mainly the indoor-restingAnopheles maculipennisS.L.，Culiseta annulataandCulex PipiensS.L.）。这些标本中有百分之十包含血餐。从其中，在964个标本中确定了宿主的血餐起源。

血液粉源

Mosquitoes had fed on nineteen different hosts, comprising 14 birds and five mammals. As only one native bird – the pigeon – has previously been identified as a host in the UK, the bird results were particularly welcome. Intriguingly, one host was the dark-breasted barn owl, asub-species（（Tyto Alba Guttata）当地白胸的种类，不知道该地区是从欧洲大陆到英国东海岸的访客。

This finding demonstrates the potential for blood meal analysis to be used as a tool for tracking rare species for conservation purposes. Two long-distance migratory birds – the yellow wagtail and barn swallow – were also identified as hosts. Migratory birds have been implicated in the long-distance dispersal and introduction of mosquito-borne pathogens to other parts of the world and are considered a potential way for novel pathogens to enter the UK.

What determines blood meal source?

令人惊讶的是，任何标本都没有鉴定出人类的血液粉。我们从其他研究（和个人经验！）中知道，人类很容易被现场蚊子咬住。因此，这一结果可能反映了宿主可用性在确定蚊子进食行为中的重要性。在峰值（crepuscular）咬合时间（刺耳）期间，该地区通常不到10人，因此在这项研究中，人类血液粉的相对比例可能太低了。

Indeed, current evidence indicates that whilst certain mosquito species may preferentially take blood meals from some hosts or host groups over others, the evidence for this being a solely intrinsic (i.e. genetic) vs. an environmental phenomenon (e.g. due to the availability of hosts) is less clear-cut.

在这里，在同一研究领域，例如Culex Pipiensformpipiens仅在鸟类（13种）上喂养，而其他亚螺旋藻，在哺乳动物（5种）和鸟类（2种）上更广泛地喂食。有趣的是，几乎全部An. atroparvus从鸡舍中收集的鸡喂食，而在其他陷阱地点以鸡和其他鸟类为食的鸡肉，在文献中更广泛地受到限制。

这说明了通过收集方法和位置引入的偏见，这使血液粉研究结果的解释变得复杂。有关此主题的有用评论here。

The importance of determining blood-feeding behaviour

The rapid and destructive emergence of the Zika virus in South America has demonstrated the continued relevance of mosquito-borne disease worldwide. Amassing data on mosquito behaviour in currently disease-free areas such as the UK will better facilitate control efforts in the event of emergence.

我的结论

为了回到我的原始问题，这项研究发现，与农场相关的蚊子以各种牲畜和野生动植物物种为食。本研究产生的数据贡献了有关禽类物种的重要信息，这些信息可能会将蚊子传播的病原体引入英国，以及在此引入后可能参与局部传播周期的那些动物和蚊子。最后，我希望在这项研究中成功使用静止盒，将鼓励其他人在未来的喂养血液行为的研究中部署这些简单而有效的收集设备。