Seasonal Dynamics, Parity Rate, and Composition ofCulicoides(Diptera: Ceratopogonidae) Occurring in the Vicinity of Wild and Domestic Ruminants in the Czech Republic

Abstract

In the light of the emergence of bluetongue and Schmallenberg viruses in northern and central Europe, an extensive entomological survey within the framework of a bluetongue control program was undertaken from 2008 to 2013 in the Czech Republic to investigate Culicoides biting midges (Diptera: Ceratopogonidae) collected in close proximity of domestic livestock and semiwild ruminants. Insects were sampled using CDC black-light suction traps placed overnight near ruminants in farms or in forest game preserves to provide data on Culicoides fauna collected near these two groups of hosts inhabiting different environments. From almost a half million biting midge specimens collected at 41 sampling sites, 34 species were identified including three species newly recorded for the Czech Republic: Culicoides (Oecacta) clastrieri Callot, Kremer & Deduit, Culicoides (Oecacta) odiatus Austen, and Culicoides (Pontoculicoides) saevus Kieffer. The Culicoides obsoletus species group, incriminated as a bluetongue virus vector, was predominant in both domestic livestock (91%) and semiwild game (52%). A relatively high proportion (around 30%) of C. obsoletus Meigen females with pigmented abdomen (= more likely parous) was observed from spring till autumn. In contrast, adult biting midges were found to be largely absent during at least three winter months, approximately December till March, which could be considered as the biting midge vector-free period.

A first estimation of Culicoides imicola and Culicoides obsoletus/Culicoides scoticus seasonality and abundance in Europe

“…Czech Republic (Radrova et al 2015) An extensive survey was done between 2008 and 2013 at 34 sampling sites using CDC black-light suction traps that were placed overnight near ruminants in farms or in forest game preserves. The…”

Red deer (Cervus elaphus) Did Not Play the Role of Maintenance Host for Bluetongue Virus in France: The Burden of Proof by Long-Term Wildlife Monitoring and Culicoides Snapshots

“…The role of Culicoides as vector species in wildlife has been limitedly investigated in the Palearctic region, excepted in relation to avian parasites transmission in wild bird populations [5]. In Europe, entomological studies have been carried out in both farms and game preserves in Spain [6] and in the Czech Republic [7]. In Spain, the species composition seems more influenced by the climate (dominance of Culicoides imicola under the southern Mediterranean climate, and of morphologically close species Culicoides obsoletus s.l.…”

“…In the Czech Republic, species belonging to the Avaritia and, at a much lesser extent, to the Culicoides subgenera were dominant in farms (~97% of the collected Culicoides ) and abundant in game preserves (~64%). Game preserves were associated with forest species such as Culicoides pallidicornis (~19%), Culicoides furcillatus (~3%), and Culicoides festivipennis (2%), often rare in farms [7]. These studies demonstrated that, under Mediterranean, oceanic, or wet continental climates, several Culicoides species, recognized as probable BTV vectors and belonging to the Avaritia and Culicoides subgenera, could be abundant in both farms and game preserves [6,7], where they are able to feed on wild ruminants [8].…”

“…Game preserves were associated with forest species such as Culicoides pallidicornis (~19%), Culicoides furcillatus (~3%), and Culicoides festivipennis (2%), often rare in farms [7]. These studies demonstrated that, under Mediterranean, oceanic, or wet continental climates, several Culicoides species, recognized as probable BTV vectors and belonging to the Avaritia and Culicoides subgenera, could be abundant in both farms and game preserves [6,7], where they are able to feed on wild ruminants [8]. These results allowed hypothesizing that Culicoides associated with domestic ruminants and farm environments are able to act as bridge vectors and transfer BTV from domestic to wild ruminant populations.…”

The Absence of Abdominal Pigmentation in Livestock Associated Culicoides following Artificial Blood Feeding and the Epidemiological Implication for Arbovirus Surveillance

“…According to this regulation, a vector-free period is defined as the total absence of C. imicola, and less than five parous females of any other observed Culicoides vector species collected in light traps [23]. Monitoring of the parous rates in field populations contributes to an understanding of adult survival rates [24] and the voltinism of vector species [25,26].…”