Background: The Culicoides obsoletus species complex (henceforth 'Obsoletus complex') is implicated in the transmission of several arboviruses that can cause severe disease in livestock, such as bluetongue, African horse sickness, epizootic hemorrhagic disease and Schmallenberg disease. Thus, this study aimed to increase our knowledge of the composition and genetic diversity of the Obsoletus complex by partial sequencing of the cytochrome c oxidase I (cox1) gene in poorly studied areas of Spain.
Methods: A study of C. obsoletus populations was carried out using a single-tube multiplex polymerase chain reaction (PCR) assay that was designed to differentiate the Obsoletus complex sibling species Culicoides obsoletus and Culicoides scoticus, based on the partial amplification of the cox1 gene, as well as cox1 georeferenced sequences from Spain available at GenBank. We sampled 117 insects of the Obsoletus complex from six locations and used a total of 238 sequences of C. obsoletus (ss) individuals (sampled here, and from GenBank) from 14 sites in mainland Spain, the Balearic Islands and the Canary Islands for genetic diversity and phylogenetic analyses.
Results: We identified 90 C. obsoletus (ss), 19 Culicoides scoticus and five Culicoides montanus midges from the six collection sites sampled, and found that the genetic diversity of C. obsoletus (ss) were higher in mainland Spain than in the Canary Islands. The multiplex PCR had limitations in terms of specificity, and no cryptic species within the Obsoletus complex were identified.
Conclusions: Within the Obsoletus complex, C. obsoletus (ss) was the predominant species in the analyzed sites of mainland Spain. Information about the species composition of the Obsoletus complex could be of relevance for future epidemiological studies when specific aspects of the vector competence and capacity of each species have been identified. Our results indicate that the intraspecific divergence is higher in C. obsoletus (ss) northern populations, and demonstrate the isolation of C. obsoletus (ss) populations of the Canary Islands.
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http://dx.doi.org/10.1186/s13071-021-04841-z | DOI Listing |
Med Vet Entomol
October 2024
Animal Health Department, NEIKER-Basque Institute for Agricultural Research and Development, Basque Research and Technology Alliance (BRTA), Derio, Spain.
Culicoides biting midges (Diptera: Ceratopogonidae) are known vectors of multiple arboviruses of veterinary and medical importance, as well as avian haemosporidian parasites. Despite their significant role as vectors, the distribution of Culicoides species in non-farmland habitats remains largely unknown. We conducted a study to assess the species community composition, abundance, and host feeding patterns of Culicoides biting midges in urban ecosystems in northern Spain.
View Article and Find Full Text PDFMed Vet Entomol
December 2024
Leibniz Centre for Agricultural Landscape Research, Müncheberg, Germany.
Culicoides biting midge species (Diptera: Ceratopogonidae) of the Obsoletus Group and the Pulicaris Complex are considered the major vectors of bluetongue and Schmallenberg viruses in Europe. Overwintering strategies of these arboviruses are controversially discussed, with the ongoing activity of vector species and a non-disrupted transmission cycle during winter being a plausible explanation. Although data on Culicoides winter activity are relatively scant, a seasonal vector-free period (SVFP), during which adult Culicoides are not or hardly active, is questionable.
View Article and Find Full Text PDFParasit Vectors
August 2024
Estación Biológica de Doñana (EBD, CSIC), Seville, Spain.
Risk Anal
July 2024
Laboratoire de Biométrie et Biologie Évolutive, UMR 5558, Université Claude Bernard Lyon 1, CNRS, VetAgro Sup, Villeurbanne, France.
Genes (Basel)
March 2024
Friedrich-Loeffler-Institut (FLI), Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald, Germany.
The emergence of culicoid-transmitted bluetongue and Schmallenberg viruses in several European countries demonstrated the ability of indigenous biting midge species to transmit pathogens. Entomologic research programs identified members of the Obsoletus Group ( subgenus ) as keyplayers in disease epidemiology in Europe. However, morphological identification of potential vectors is challenging due to the recent discovery of new genetic variants (haplotypes) of sensu stricto (s.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!