研究食血昆虫的宿主摄食行为对于评估媒介传播疾病的传播途径至关重要。了解某些物种是否具有嗜鸟或嗜乳性摄食行为,可以促进未来的研究,重点是病原体在某些宿主物种之间的传播。Latreille(双翅目:Ceratopogenidae)是几种病原体的载体,其中包括虫媒病毒,细菌和寄生虫相当多样的脊椎动物宿主。然而,大多数研究集中在摄食习惯上,目标是可以传播蓝舌病毒的Culicoides物种,因此,有一种嗜奶性的摄食行为,撇开与媒介传播的寄生虫向鸟类传播有关的库利科伊德物种,如克鲁斯血液变形杆菌(Haemosporida:血液变形杆菌科)。这项研究旨在使用基于分子的方法调查野生捕获的Culicoides的血粉来源,并将我们的发现与Culicoides物种中的疟原虫寄生虫的报道相关联。2021-2023年,在立陶宛的七个不同地区使用紫外线(UV)光陷阱收集了成年的Culicoides雌性。咬人的mid被解剖,充血雌性的腹部用于血粉来源的分子研究。使用扩增脊椎动物细胞色素B基因片段的聚合酶链反应(PCR)方案。将获得的序列与GenBank数据库中的可用信息进行比较以确认血粉的来源。总的来说,258名充盈的Culicoides雌性,代表九个不同的物种,进行了分析。其中29.1%确定了血粉的来源,其中大多数昆虫以鸟类为食(74.7%),其余以哺乳动物为食(25.3%)。CulicoidessegnisCampbell,Pelham-Clinton是唯一只以鸟类为食的物种;来自Obsoletus组的Culicoides,C.pallidicornisKieffer和C.punctatusLatreille被发现专门以哺乳动物为食;C.festivpennisKieffer,kibunensisTokunaga和c.pictipennisStaeger具有机会主义的进食行为,前两者最好以鸟类为食。由于它们的摄食行为和文献中报道的疟原虫的存在,C.节日,C.kibunensis,C.pictipennis,和C.segnis在野生鸟类媒介传播寄生虫的传播中起着重要作用。这些Culicoides物种已经被证实能够支持几种Seemoproteus物种和谱系的发展。未来的研究集中在了解由Culicoides传播的禽类病原体的流行病学上,应针对这些物种。
Investigations of host feeding behaviour in haematophagous insects are critical to assess transmission routes of vector-borne diseases. Understanding if a certain species has ornithophilic or mammalophilic feeding behaviour can facilitate future studies focused on pathogens transmission to and from certain host species. Culicoides Latreille (Diptera: Ceratopogonidae) are vectors of several pathogens, which include arboviruses, bacteria and parasites to a considerable diversity of vertebrate hosts. However, most of the studies focused on feeding habits target Culicoides species that could transmit the Bluetongue virus, consequently with a mammalophilic feeding behaviour, leaving aside the Culicoides species that are involved in the transmission of vector-borne parasites to birds, such as Haemoproteus Kruse (
Haemosporida: Haemoproteidae). This study aimed to investigate the source of blood meals of wild-caught Culicoides using molecular-based methods and to correlate our findings with the reports of Haemoproteus parasites in Culicoides species. Engorged Culicoides females were collected using ultraviolet (UV)-light traps at seven different localities in Lithuania in 2021-2023. Biting midges were dissected, and the abdomens of engorged females were used for molecular investigation of the blood meal source. A polymerase chain reaction (PCR) protocol that amplifies a fragment of the Cytochrome B gene of vertebrates was used. Obtained sequences were compared to available information in GenBank database to confirm the source of the blood meal. In total, 258 engorged Culicoides females, representing nine different species, were analysed. The source of blood meal was identified in 29.1% of them with most of the insects having fed on birds (74.7%) and the remaining on mammals (25.3%). Culicoides segnis Campbell, Pelham-Clinton was the only species to feed exclusively on birds; Culicoides from the Obsoletus group, C. pallidicornis Kieffer and C. punctatus Latreille were found to feed exclusively on mammals; C. festivipennis Kieffer, C. kibunensis Tokunaga and C. pictipennis Staeger had an opportunistic feeding behaviour, with the first two preferably feeding on birds. Due to their feeding behaviour and the presence of Haemoproteus parasites reported in the literature, C. festivipennis, C. kibunensis, C. pictipennis, and C. segnis play an important role in the transmission of those avian vector-borne parasite in the wild. These Culicoides species were already confirmed as being able to support the development of several Haemoproteus species and lineages. Future studies focused on understanding the epidemiology of avian pathogens transmitted by Culicoides should target these species.