Kalyanasundaram Aravindan, Henry Cassandra, Brym Matthew Z, Kendall Ronald J
The Wildlife Toxicology Laboratory, The Institute of Environmental and Human Health, Texas Tech University, Box 43290, Lubbock, TX, 79409-3290, USA.
Parasitol Res. 2018 Sep;117(9):2963-2969. doi: 10.1007/s00436-018-5993-5. Epub 2018 Jul 7.
Physaloptera spp. are common nematodes found in the stomach and muscles of mammals, reptiles, amphibians, and birds. Physaloptera spp. have a complicated life cycle with multiple definitive hosts, arthropod intermediate hosts, aberrant infections, and possible second intermediate hosts or paratenic hosts. For example, Physaloptera sp. larvae have been found within the tissues of wild northern bobwhite quail (Colinus virginianus), and it is suspected that quail may serve as paratenic or secondary hosts of these parasites. However, because it is not known what role quail play in the life cycle of Physaloptera spp. and descriptions of Physaloptera spp. larvae are limited, molecular tools may be beneficial when identifying these helminths. In this study, we generated primers using universal nematode primers and obtained a partial mitochondrial cytochrome oxidase 1 (COX 1) sequence. Morphological identification of Physaloptera sp. in bobwhite was confirmed via polymerase chain reaction (PCR), and a phylogenetic tree was constructed using the maximum likelihood method. BLAST analysis revealed a strong identity to other Physaloptera spp. and the phylogenetic tree placed all Physaloptera spp. in the same cluster. We also documented a marked increase in Physaloptera infections in bobwhite from 2017 to 2018, and the similarity of these parasites to Onchocerca volvulus and Wuchereria bancrofti may give insight into the increased prevalence we observed. This study demonstrates the usefulness of molecular techniques to confirm the identity of species that may lack adequate descriptions and provides new insight for the diagnosis and potentially overlooked significance of Physaloptera sp. infections of bobwhite in the Rolling Plains ecoregion of Texas.
泡翼属线虫是在哺乳动物、爬行动物、两栖动物和鸟类的胃和肌肉中发现的常见线虫。泡翼属线虫具有复杂的生命周期，有多个终末宿主、节肢动物中间宿主、异常感染以及可能的第二中间宿主或转续宿主。例如，在野生北部 Bobwhite 鹌鹑（Colinus virginianus）的组织内发现了泡翼属线虫幼虫，并且怀疑鹌鹑可能是这些寄生虫的转续宿主或第二宿主。然而，由于尚不清楚鹌鹑在泡翼属线虫生命周期中所起的作用，且泡翼属线虫幼虫的描述有限，因此在鉴定这些蠕虫时分子工具可能会有所帮助。在本研究中，我们使用通用线虫引物生成了引物，并获得了部分线粒体细胞色素氧化酶 1（COX 1）序列。通过聚合酶链反应（PCR）证实了 Bobwhite 鹌鹑中泡翼属线虫的形态学鉴定，并使用最大似然法构建了系统发育树。BLAST 分析显示与其他泡翼属线虫有很强的同源性，并且系统发育树将所有泡翼属线虫置于同一聚类中。我们还记录了 2017 年至 2018 年 Bobwhite 鹌鹑中泡翼属线虫感染显著增加，并且这些寄生虫与盘尾丝虫和班氏吴策线虫的相似性可能有助于深入了解我们观察到的发病率增加情况。本研究证明了分子技术在确认可能缺乏充分描述的物种身份方面的有用性，并为德克萨斯州滚动平原生态区 Bobwhite 鹌鹑泡翼属线虫感染的诊断和潜在被忽视的重要性提供了新的见解。
