Morphological and Molecular Characteristics of the Gastro-Intestinal Nematode Parasite Ascaridia columbae Infecting the Domestic Pigeon Columba livia domestica in Saudi Arabia

Abstract

Background Parasitism is a complex problem that is often ignored in companion animals, including birds, unless it develops into a severe clinical disorder. The present study was, therefore, aimed to investigate the presence of the gastrointestinal nematode infecting the domestic pigeon and provide a complete morphological description and clarify its taxonomic position through phylogenetic analysis of the ITS1-5.8s-ITS2 rDNA gene region. Materials and MethodsDuring the current study, a total of twenty-six domestic pigeons, Columba livia domestica, were collected and internal organs examined for helminth detection. Using light and scanning electron microscopy, the recovered parasite species are studied. In addition, the selected gene region was obtained and sequenced using appropriate primers that aid in the formation of the phylogenetic dendrogram for the recovered parasite species with others retrieved from GenBank. Results Morphological examination showed that this nematode parasite belongs to the Ascaridiidae family within the genus Ascaridia. The material was assigned to the previously described Ascaridia columbae by providing all the characteristic features as the presence of a mouth opening surrounded by three tri-lobed lips; each lip has two triangular teeth with a spoonlike structure, cephalic papillae and amphidal pores on lips surface, presence of lateral cuticular alae and pre-cloacal sucker, 10 pairs of caudal papillae, and two equal spicules in male worms. The morphological investigations of this species were supplemented by molecular analysis of ITS1-5.8s-ITS2 rDNA gene region. The data showed that the present A. coulmbae is deeply embedded in the Ascaridia genus with a 74-99% sequence similarity to other species in the Chromadorea class. Ascaridiidae appears as monophyly and represented as a sister group to Heterakidae. The ascaridiid species examined belong to the Ascaridia genus and displaced a close relationship with the previously described A. coulmbae (gb| KF147909.1, gb| AJ001509.1, gb| KC905082.1, gb| JQ995321.1, gb| JX624729.1) as putative sister taxa. Conclusion The present study revealed that the species Ascaridia is the first account of this genus as an endoparasite from the domestic pigeon inhabiting Saudi Arabia. Therefore, the combination of morphological and molecular studies helps to identify this species correctly and identified as Ascaridia columbae.

Morphological and molecular characterization of Ascaridia columbae in the domestic pigeon (Columba livia domestica) and the assessment of its immunological responses

“…The identification of A. columbae depends on ultramicroscopic identification of the nematode and analysis of the ITS gene; this study reveals that the morphological identification confirmed the infection of examined pigeon with A. columbae nematod. In this study; the morphological identification was similar to a previous study recorded by Al Quraishy et al. 2020 ; which studied the A. columbae by SEM, which based upon different characteristic features that confirm the recovered nematod is A. columbae ; these features are (well-developed lips; a cuticular organization with the presence of transverse annuli; pre-cloacal sucker the number and distribution of the cloacal papillae; a vulva near the middle region of the body) this study similar as Khalil et al.…”

“…Our study in molecular characterization used the PCR sequencing of the (ITS1-5.8sITS2) of the rDNA gene region, which confirmed that the collected Ascidida belongs to A. columbae nematod. A similar study was recorded by Al Quraishy et al. 2020 (A. columbae) and Gomes et al.…”

“…2020 ; which studied the A. columbae by SEM, which based upon different characteristic features that confirm the recovered nematod is A. columbae ; these features are (well-developed lips; a cuticular organization with the presence of transverse annuli; pre-cloacal sucker the number and distribution of the cloacal papillae; a vulva near the middle region of the body) this study similar as Khalil et al. 2014 ; Al Quraishy et al. 2020 .…”

“…2015 ( Ancylostoma buckleyi, Pterigodermatites pluripectinata, and Ascaridia galli ). The moleculer approach in A. columbae revealing that the genus Ascaridia and is closely related and within the A. columbae species among Ascaridiidae (MZ343369) as recorded by Al Quraishy et al. (2020) .…”

Parasites of domestic and wild pigeons in the south of Ukraine

“…It is also possible that domestic pigeons may serve as alternative hosts for some poultry helminths with which they interact and are closely related phylogenetically (Michel, 1974). Helminths that are localized in the intestines of birds significantly affect the functional activity of the immune system, cause immunodeficiency, reduce the natural reactivity of the infected organism (Biswal et al, 2016;Al Quraishy et al, 2020).…”