The morphological and molecular characterization of Baylisascaris devosi Sprent, 1952 (Ascaridoidea, Nematoda), collected from Pine marten (Martes martes) in Iran

Meysam Sharifdini,Fattaneh Mikaeili,Richard A Heckmann

doi:10.1186/s13071-020-04513-4

Abstract

BackgroundBaylisascaris devosi is an intestinal nematode found in several carnivores including fisher, wolverine, Beech marten, American marten and sable in different parts of the world, but this nematode has not been reported from Pine marten. Therefore, this study aimed to identify Baylisascaris isolated from a Pine marten in Iran using morphological and molecular approaches.MethodsSpecimens of B. devosi were collected from one road-killed Pine marten in northern Iran. Morphological features were evaluated using scanning electron microscopy, energy dispersive x-ray analysis and ion sectioning. The molecular characterization was carried out using partial Cox1, LSU rDNA and ITS-rDNA genes.ResultsThe nematodes isolated from the Pine marten were confirmed to be B. devosi based on the morphological features and the sequence of ribosomal and mitochondrial loci. X-ray scans (EDAX) were completed on gallium cut structures (papillae, eggs, male spike and mouth denticles) of B. devosi using a dual-beam scanning electron microscope. The male spike and mouth denticles had a high level of hardening elements (Ca, P, S), helping to explain the chemical nature and morphology of the worm. Based on these genetic marker analyses, our sequence had the greatest similarity with Russian B. devosi isolated from sable.ConclusionsIn this study, to our knowledge, the occurrence of B. devosi infection in Pine marten is reported for the first time. Molecular analysis showed that these three genes are suitable molecular markers for identification and inferring phylogenetic relationships of Baylisascaris species. Furthermore, the high divergence of Cox1 between Baylisascaris species indicates that Cox1 could be used for their phylogenetic and taxonomic studies.Graphical

Highlights

Baylisascaris devosi is an intestinal nematode found in several carnivores including fisher, wolverine, Beech marten, American marten and sable in different parts of the world, but this nematode has not been reported from Pine marten
Human is an accidental host for this parasite, and baylisascariasis in human can be caused by B. procyonis, B. columnaris, B. melis, B. devosi, B. transfuga and B. tasmaniensis [3]
Observation with the scanning electron microscope showed that the triangular mouth of B. devosi was surrounded by three lips; one of the lips was located in dorsal position and the other two in the ventral position (Fig. 1a, b)

Summary

Introduction

Baylisascaris devosi is an intestinal nematode found in several carnivores including fisher, wolverine, Beech marten, American marten and sable in different parts of the world, but this nematode has not been reported from Pine marten. This study aimed to identify Baylisascaris isolated from a Pine marten in Iran using morphological and molecular approaches. Baylisascaris is a roundworm belonging to the family Ascarididae that has several species, including B. procyonis, B. melis, B. transfuga, B. columnaris, B. devosi, B. laevis, B. shroederi, B. venezuelensis and B. potosis. The various species of Baylisascaris have specific definitive hosts and can be identified [1]. Unembryonated eggs are shed in the feces of the definitive host and become infective in the environment within several weeks. Human is an accidental host for this parasite, and baylisascariasis in human can be caused by B. procyonis, B. columnaris, B. melis, B. devosi, B. transfuga and B. tasmaniensis [3]. Since baylisascariasis is diagnosed by serological methods and these cannot identify the parasite species, molecular methods are useful for the identification of Baylisascaris species [3]

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