Dimitrov Dimitar, Valkiūnas Gediminas, Zehtindjiev Pavel, Ilieva Mihaela, Bensch Staffan
Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113 Sofia, Bulgaria.
Zootaxa. 2013;3666:369-81. doi: 10.11646/zootaxa.3666.3.7.
In studies of haemosporidian systematics and taxonomy, a combination of microscopic examination and molecular identification has been recommended. The yellow wagtail (Motacillaflava) is a frequently used species in studies of host-parasite interactions; blood parasites of this bird have been well studied using microscopic examination of blood films, but data on molecular characterization of the parasites are scattered. Here we present the first study linking several haemosporidian cyt b sequences with their morphospecies parasitizing the yellow wagtail, combining light microscopy and nested PCR methods. The lineage hYWT1 of Haemoproteus motacillae was the most prevalent parasite; it was recorded in 38% of the birds. The latter lineage and the lineages hYWT2, hYWT3, hYWT5 and hYWT6 form a well-supported clade on the phylogenetic tree and likely represent intraspecific genetic variation of H. motacillae, with genetic divergence of 0.3 - 1.5 % among these lineages. Microscopic examination of smears prepared during an in vitro experiment, which was designed for observation of developing ookinetes, showed that H. motacillae ookinetes were present 5 hours after exposure of blood to air at 18-20° C. Ookinetes of this parasite belong to a group of large Haemoproteus spp. ookinetes (19.9 µm in length on average). Illustrations of the parasites are given. Two of reported Plasmodium lineages, pCOLLI and pYWT4 are phylogenetically closely related to the widespread host generalist parasites Plasmodium relictun (cyt b lineages pSGS 1, pGRW4 and pGRW11), but it was not possible to establish this morphologically. This study contributes to the molecular identification of avian haemosporidian parasites and provides information on morphology of H. motacillae ookinetes, which is additional information assisting the microscopic identification of this species.
在血孢子虫系统学和分类学研究中，建议结合显微镜检查和分子鉴定。黄鹡鸰（Motacilla flava）是宿主 - 寄生虫相互作用研究中常用的物种；通过对血涂片进行显微镜检查，对这种鸟类的血液寄生虫进行了充分研究，但关于这些寄生虫分子特征的数据较为分散。在此，我们首次将几种血孢子虫细胞色素b序列与其寄生于黄鹡鸰的形态物种联系起来，结合了光学显微镜和巢式PCR方法。Motacillae血变原虫的hYWT1谱系是最普遍的寄生虫；在38%的鸟类中被记录到。后一谱系以及hYWT2、hYWT3、hYWT5和hYWT6谱系在系统发育树上形成了一个得到充分支持的分支，可能代表Motacillae血变原虫的种内遗传变异，这些谱系之间的遗传差异为0.3 - 1.5%。在一项为观察发育中的动合子而设计的体外实验中，对涂片进行显微镜检查发现，在18 - 20°C下血液暴露于空气中5小时后出现了Motacillae血变原虫动合子。这种寄生虫的动合子属于大型血变原虫属动合子组（平均长度为19.9 µm）。给出了寄生虫的图示。报告的两种疟原虫谱系pCOLLI和pYWT4在系统发育上与广泛存在的宿主泛化寄生虫残疟原虫（细胞色素b谱系pSGS 1、pGRW4和pGRW11）密切相关，但无法通过形态学确定这一点。本研究有助于鸟类血孢子虫寄生虫的分子鉴定，并提供了Motacillae血变原虫动合子形态的信息，这是辅助该物种显微镜鉴定的额外信息。
