Several species of Trichuridae nematodes can infect dogs, cats and wild mammals. The diagnosis of these infections relies on the microscopic identiﬁcation of eggs which are characterized by a similar “lemon” shape and polar plugs in all Trichuridae. Thus, morphological diagnosis to species level is challenging. The use of biomolecular diagnostic methods is desirable but very little genetic data are known from Trichuridae of carnivores and small mammals. The aim of this work was to genetically characterize several species of Trichuridae that can affect dogs, cats and wild mammals, as a basis to develop molecular diagnostic tests. Specimens (adult worms or eggs) of Eucoleus aerophilus (syn. Capillaria aerophila), Eucoleus boehmi (syn. Capillaria boehmi), Pearsonema plica (syn. Capillaria plica), Aonchotheca putorii (syn. Capillaria putorii), Calodium hepaticum (syn. Capillaria hepatica), Calodium splenaecum (syn. Capillaria splenaeca) and Trichuris vulpis were obtained from carcasses of red foxes, feces of dogs, the liver of a vole and from the spleen of Crocidura sp. Parts of the small subunit rRNA (18S rRNA) gene and of the mitochondrial cytochrome c oxidase subunit I (cox 1 mtDNA) gene were ampliﬁed from the above mentioned nematodes, yielding the ﬁrst 18S rRNA gene sequences of all the capillariid nematodes and the ﬁrst cox 1 mtDNA sequences of E. boehmi, P. plica, C. hepaticum, A. putorii and T. vulpis. The 18S rRNA gene is highly conserved among the different species and not suitable as a target for speciﬁc diagnostic oligonucleotides. However, these sequences contribute to a better understanding of the complex taxonomic relations among Trichuridae. Indeed, a dendrogram based on the 18S rRNA gene locus supports the latest taxonomic revision. Interspecies divergence was much higher at the cox 1 mtDNA gene locus, rendering it suitable for DNA barcoding and particularly valuable in resolving closely related species. Furthermore, the mitochondrial genetic markers deﬁned in the present study are useful to develop Trichuridae species-speciﬁc primers.
|Autori:||Guardone, L.; Deplazes, P.; Macchioni, Fabio; Magi, Marta; Mathis, A.|
|Titolo:||Ribosomal and mitochondrial DNA analysis of Trichuridae nematodes of carnivores and small mammals|
|Anno del prodotto:||2013|
|Digital Object Identifier (DOI):||10.1016/j.vetpar.2013.06.022|
|Appare nelle tipologie:||1.1 Articolo in rivista|