scholarly journals Comparaison de l'efficacité de quatre modèles de pièges lumineux pour la collecte de Culicoides piqueurs en Allemagne

2009 ◽  
Vol 62 (2-4) ◽  
pp. 139 ◽  
Author(s):  
Christophe Probst ◽  
Helge Kampen ◽  
D. Werner ◽  
Jörn M. Gethmann ◽  
Franz J. Conraths ◽  
...  
Keyword(s):  
Latin Square ◽  
Economic Losses ◽  
Animal Disease ◽  
Light Traps ◽  
Biting Midges ◽  
Livestock Species ◽  
Bluetongue Disease ◽  
Set Up ◽  
Pièges Lumineux ◽  
Obsoletus Complex

Biting midges of the genus Culicoides are vectors of bluetongue disease, an OIE-listed animal disease which has recently led to severe economic losses in susceptible livestock species in Europe. Therefore, several affected countries conduct monitor­ing programmes for Culicoides spp. To compare the number and species composition of Culicoides obtained, the efficacy of various traps used to collect biting midges needs to be assessed. Four aspiration black light traps were thus compared: the Onderstepoort, John W. Hock, Riebt, and Biogents. One of the traps was operated from the 1st of April 2009 to determine the onset of increased Culicoides activity and thus the best time to start the study. The comparison was carried out from May 16th until September 26th. The traps were set up at four different sites on pastures of the Friedrich-Loeffler-Institut where cattle, sheep and goats were present. The comparison was carried out according to the Medreonet protocol in a 4×4 randomized Latin square design with one night of activity for each trap at each site. The highest number of Culicoides specimens was captured by the Onderstepoort (1245), followed by the Biogents (365), the Hock (30) and the Riebt (4) traps. The majority of midges caught was classified as belonging to the Obsoletus complex (1399), including C. obsoletus s.s., C. scoticus and C. chiopterus. Other encountered species were C. punctatus s.s. (87), C. albicans (78) and C. riethi (50). Most biting midges were collected in May (594) and June (575). In September only one Culicoides speci­men was caught. The results show that the trap model has a great impact on the number of Culicoides caught. Culicoides monitor­ing programmes should be harmonised by using the same type of trap everywhere or by adjusting the numbers of collected biting midges using a trap factor. The trap model should be taken into consideration in the decision to declare the seasonally-determined vector-free periods.

scholarly journals Evaluation de la stabulation comme moyen de protection des bovins des piqûres de Culicoides, vecteurs de la fièvre catarrhale ovine

2009 ◽  
Vol 62 (2-4) ◽  
pp. 99
Author(s):  
M. Baylis ◽  
H. Parkin ◽  
K. Kreppel ◽  
Simon Carpenter ◽  
P.S. Mellor ◽  
...  
Keyword(s):  
Light Trap ◽  
Latin Square ◽  
Strongly Correlated ◽  
Biting Midges ◽  
Maximum Wind ◽  
Wind Speeds ◽  
North Wales ◽  
The Difference ◽  
Trap Catches ◽  
Obsoletus Complex

Light-trap catches of Culicoides biting midges were compared inside and outside animal housing, in the presence and in the absence of cattle. A three-time replicated 4x4 Latin square design was used at four farms in Bala, North Wales, over 12 nights in May and June; the experiment was repeated in October. In the two studies, over 70,000 and over 4500 Culicoides were trapped of which 93% and 86%, respectively, belonged to C. Obsoletus complex. Across the four farms, in May and June, the presence of cattle increased catches of C. obsoletus by 2.3 times, and outside traps caught them 6.5 times more than inside traps. Similar patterns were apparent in October, but the difference between inside and outside catches was reduced. Catches were strongly correlated with minimum temperature and maximum wind speed, and these two variables explained a large amount of night-to-night variation in catch. Outside catches were reduced to a greater extent than inside catches by colder minimum tem­peratures and stronger maximum wind speeds. These conditions occurred more frequently in October than in May and June, thereby suppressing the outside catches more than the inside catches, and reducing the apparent degree of exophily of C. obsoletus in autumn. The results suggest that the risk of animals receiving bites from C. obsoletus is reduced by housing at both times of year, but the benefit would be greatest on warm, still nights when outside catches are at their greatest.

scholarly journals Variabilité spatiale des captures de Culicoides dans des fermes de la zone de Bala au nord du Pays de Galles

2009 ◽  
Vol 62 (2-4) ◽  
pp. 103 ◽  
Author(s):  
Hélène Guis ◽  
Karien Labuschagne ◽  
David Sugden ◽  
K. M. McIntire ◽  
Maria J. Vilar ◽  
...  
Keyword(s):  
Sampling Design ◽  
Local Scale ◽  
Environmental Data ◽  
Culicoides Species ◽  
Light Traps ◽  
Breeding Sites ◽  
Vector Abundance ◽  
North Wales ◽  
Set Up ◽  
Obsoletus Complex

The aim of this study was to investigate the spatial variability of Culicoides catches at a local scale using environmental data and farm characteristics. A thrice-replicated random sampling design was set up on a 1x1 km grid in a 6x6 km study site in Bala, North Wales in July 2008 over a period of 12 days using Onderstepoort black light traps to catch Culicoides. Overall, 132 catches were made on 35 farms, 32 of which were sampled three times and three of which were sampled daily. A total of 357,229 Culicoides encompassing 19 species (mean catch = 2706 per trap and per night; maximum catch = 65,763) were caught. The species of the Obsoletus complex accounted for 62% of the catches. Environmental factors (such as land cover, land use, soil type, altitude and weather) and farm characteristics (animals, insecticide use, dung management, proximity to water and to potential breeding sites, and openness of the landscape) will be used to model the abundance of Culicoides species. The influ­ence of Culicoides abundance in neighbouring farms will also be assessed and accounted for. This will help better understand spa­tial distribution and variability of Culicoides densities at a local scale and provide elements for discussion on how to approach mapping and modelling of vector abundance at coarser scales.

scholarly journals Répartition et abondance des moucherons piqueurs, vecteurs potentiels de la fièvre catarrhale ovine, en Suisse

2009 ◽  
Vol 62 (2-4) ◽  
pp. 129
Author(s):  
C. Kaufmann ◽  
C. Schaffner ◽  
A. Tschuor ◽  
A. Mathis
Keyword(s):  
Vector Competence ◽  
Northern Europe ◽  
Light Traps ◽  
Biting Midges ◽  
Climatic Regions ◽  
Monthly Average ◽  
The Third ◽  
Virus Serotype ◽  
Agricultural Areas ◽  
Obsoletus Complex

Indigenous biting midges proved to be highly efficient vectors for the recently introduced bluetongue virus serotype 8 (BTV-8). Since its introduction in Northern Europe, the virus has rapidly spread, reaching Switzerland in 2008. The aims of this project are to determine the distribution, abundance, and activity pat­terns of biting midges occurring in Switzerland. Insects were caught with Onderstepoort ultraviolet light traps once weekly at stations representing the 12 climatic regions of Switzerland throughout the whole year. In addition, catches were carried out at five stations in an Alpine region of Switzerland at alti­tudes between 1300 and 2000 metres above sea level from the end of June to the end of October 2008. Midges were grouped under the stereomicroscope into Obsoletus complex, Pulicaris complex or other Culicoides spp. Midges were caught at all stations, albeit in very different numbers. The highest monthly average was 10,000 midges per night (Dittingen); the third high­est average was recorded at the highest station (Juf, 2130 m). At stations below 1500 m, midges of the Obsoletus complex (98% in Dittingen) were predominant. In Central Europe, they are considered the most likely vectors responsible for BTV trans­mission. With increasing altitude, midges of the Pulicaris com­plex prevailed (91% in Juf). Catches in two neighbouring Alpine mountains of similar altitude (approximately 2000 m) varied considerably. It is most likely that there are no midge-free zones in the agricultural areas (including Alpine summer pastures) of Switzerland, but the vector competence of the various midges with regard to BTV needs to be urgently clarified.

scholarly journals Retrospective Analysis of the Bluetongue Outbreak in Serbia

2017 ◽  
Vol 40 (1) ◽  
pp. 21-27 ◽  
Author(s):  
Spomenka Djurić ◽  
Predrag Simeunović ◽  
Milorad Mirilović ◽  
Jevrosima Stevanović ◽  
Uroš Glavinić ◽  
...  
Keyword(s):  
Bluetongue Virus ◽  
Control Measure ◽  
Infected Sheep ◽  
Economic Losses ◽  
Biting Midges ◽  
Domestic Ruminants ◽  
Investigation Period ◽  
Bluetongue Disease ◽  
Culicoides Biting Midges ◽  
Veterinary Institute

Abstract Bluetongue, a vector-born disease caused by the Bluetongue virus (BTV) and transmitted by Culicoides biting midges, is considered to be one of the most important diseases of domestic ruminants. The first outbreak of bluetongue in Serbia was reported in 2001, when BTV serotype 9 was identified in sampled materials. In 2014, outbreak of BTV-4 in Serbia caused considerable economic losses affecting sheep, cattle and goats. During this outbreak, BTV-4 was recorded in 644 outbreaks within 49 municipalities, part of 17 administrative regions. From the total number of sheep kept in areas affected by bluetongue (n=1 748 110), 2 083 cases (0.2%) were proven to be BTV-4 infected. Total of 206 infected cattle and 24 infected goats were reported during this investigation period, which represents 0.06% and 0.03% of the total number of cattle and goats kept in affected areas, respectively. The highest incidence of infected sheep, cattle and goats was recorded on the territory covered by veterinary institute of Nis. Recorded lethality in cattle, sheep and goats was 18.45% (n=38), 48.10% (n=1002) and 54.17% (n=13), respectively. The peak of the outbreak was in September and October when 94.43% of the confirmed positive cases, regardless of the species, was recorded. Monitoring of bluetongue disease in Serbia relies on active surveillance programmes aimed at: (i) identification and tracing of susceptible and potentially infected animals and (ii) detection, distribution and prevalence of insect vectors. Vaccination of sheep is planned to be implemented as a control measure against bluetongue in Serbia.

scholarly journals Culicoides insignis Lutz, 1913 (Diptera: Ceratopogonidae) Biting Midges in Northeast of Brazil

Insects ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 366
Author(s):  
Raisa Rodrigues Santos Rios ◽  
Maria Clara Alves Santarém ◽  
Karlos Antônio Lisboa Ribeiro Júnior ◽  
Breno Araujo de Melo ◽  
Sybelle Georgia Mesquita da Silva ◽  
...  
Keyword(s):  
Genetic Analysis ◽  
Dna Sequencing ◽  
Control Strategies ◽  
Northeast Brazil ◽  
Light Traps ◽  
Biting Midges ◽  
Animal Diseases ◽  
Local Species ◽  
Specific Species ◽  
Human And Animal Diseases

The species of the Culicoides genus are hematophagous, and some of them are vectors of important human and animal diseases. This group of insects is distributed worldwide, varying according to local species. Knowledge of the geographic distribution of specific species is crucial for the development and implementation of control strategies. The aim of this work was to investigate the occurrence of Culicoides in the state of Alagoas in northeast Brazil. Midges were captured with CDC light traps, and their identification and morphological analyses were performed by the Ceratopogonidae Collection of the Oswaldo Cruz Foundation (FIOCRUZ/CCER) in Rio de Janeiro, Brazil. Morphological analyses were performed using the key to Culicoides from the guttatus group and comparison with other deposited specimens. DNA sequencing, genetic analysis and comparison with sequences in the Genbank database, confirmed the identification of the flies as Culicoides insignis. This was the first formal report of C. insignis being found in Alagoas.

scholarly journals Innovative passive reinforcements for the gradual stabilization of a landslide according with the observational method

Landslides ◽  
2021 ◽  
Author(s):  
Lorenzo Brezzi ◽  
Alberto Bisson ◽  
Davide Pasa ◽  
Simonetta Cola
Keyword(s):  
Monitoring System ◽  
Low Cost ◽  
Economic Losses ◽  
Fe Model ◽  
Site Conditions ◽  
Observational Method ◽  
Rainy Period ◽  
Sustainable Solutions ◽  
Before And After ◽  
Set Up

AbstractA large number of landslides occur in North-Eastern Italy during every rainy period due to the particular hydrogeological conditions of this area. Even if there are no casualties, the economic losses are often significant, and municipalities frequently do not have sufficient financial resources to repair the damage and stabilize all the unstable slopes. In this regard, the research for more economically sustainable solutions is a crucial challenge. Floating composite anchors are an innovative and low-cost technique set up for slope stabilization: it consists in the use of passive sub-horizontal reinforcements, obtained by coupling a traditional self-drilling bar with some tendons cemented inside it. This work concerns the application of this technique according to the observational method described within the Italian and European technical codes and mainly recommended for the design of geotechnical works, especially when performed in highly uncertain site conditions. The observational method prescribes designing an intervention and, at the same time, using a monitoring system in order to correct and adapt the project during realization of the works on the basis of new data acquired while on site. The case study is the landslide of Cischele, a medium landslide which occurred in 2010 after an exceptional heavy rainy period. In 2015, some floating composite anchors were installed to slow down the movement, even if, due to a limited budget, they were not enough to ensure the complete stabilization of the slope. Thanks to a monitoring system installed in the meantime, it is now possible to have a comparison between the site conditions before and after the intervention. This allows the evaluation of benefits achieved with the reinforcements and, at the same time, the assessment of additional improvements. Two stabilization scenarios are studied through an FE model: the first includes the stabilization system built in 2015, while the second evaluates a new solution proposed to further increase the slope stability.

scholarly journals Culicoides biting midges at the National Zoological Gardens of South Africa : research communication

2007 ◽  
Vol 74 (4) ◽  
Author(s):  
K. Labuschagne ◽  
L.J. Gerber ◽  
I. Espie ◽  
S. Carpenter
Keyword(s):  
South Africa ◽  
Vector Competence ◽  
Far East ◽  
Wild Animals ◽  
Light Traps ◽  
Biting Midges ◽  
Research Communication ◽  
Culicoides Imicola ◽  
Large Numbers ◽  
Culicoides Biting Midges

Culicoides biting midges (Diptera: Ceratopogonidae) are responsible for the transmission of a large number of pathogens to livestock and wild animals. In this study the presence of the genus, using light traps based at four different sites within the National Zoological Gardens of South Africa, was investigated during 2002-2004. In total, 37 species were recorded, including large numbers of Culicoides imicola Kieffer, 1913, which is responsible for the transmission of economically important arboviruses in South Africa, Europe, Middle and Far East. These results are discussed with reference to the wider Culicoides fauna in the Onderstepoort area of South Africa, their vector competence as well as biosecurity at the National Zoological Gardens.

scholarly journals Nitrogen and Crude Proteins in Beetroot (Beta vulgaris var. conditiva) under Different Fertilization Treatments

2012 ◽  
Vol 40 (2) ◽  
pp. 215 ◽  
Author(s):  
Marko PETEK ◽  
Mirjana HERAK CUSTIC ◽  
Nina TOTH ◽  
Sanja SLUNJSKI ◽  
Lepomir COGA ◽  
...  
Keyword(s):  
Protein Content ◽  
Beta Vulgaris ◽  
Crude Protein ◽  
Latin Square ◽  
Storage Period ◽  
Dry Weight ◽  
Fresh Weight ◽  
Mineral Fertilization ◽  
Stable Manure ◽  
Set Up

The research aim was to determine the influence of different organic and mineral fertilization treatments and post-harvest treatments on the content of nitrogen and crude proteins in the edible part of beetroot (Beta vulgaris var. conditiva). A field trial (2003-2005) was set up in a hilly part of Croatia according to the Latin square method with four types of fertilization (control, 50 t ha-1 stable manure, 500 and 1000 kg ha-1 NPK 5-20-30), while treatments involved harvested fresh beetroot and stored fresh beetroot. The highest dry weight (DW) content was determined in climatologically favourable 2004 (average 14.8% DW) and in the treatment with 1000 kg ha-1 NPK 5-20-30 (15.6% DW) in harvested beetroot. In 2004 and 2005, the highest levels of nitrogen and crude proteins in harvested beetroot were determined in the treatment with 1000 kg ha-1 NPK 5-20-30 (2.41 and 2.43 g N kg-1 in fresh weight and 15.07 and 15.21 g crude proteins kg-1 in fresh weight, respectively). Regardless of fertilization treatment or studied year, nitrogen and crude protein contents were higher in stored than in harvested beetroot, by 12% on average. The lowest crude protein content was determined in treatment with stable manure what confirmed that protein content decreased by organic fertilization. It can be concluded that beetroot lost some water during the storage period, which increased its content of nitrogen and crude proteins in fresh weight and thus increased the nutritional quality of beetroot as a functional food.

scholarly journals Comparing Different Larval Food Sources and Temperature Regimes for the Rearing of Culicoides obsoletus/scoticus Complex Midges, the Predominant Bluetongue, and Schmallenberg Virus Vectors in Northern Europe

Proceedings ◽  
2020 ◽  
Vol 50 (1) ◽  
pp. 80
Author(s):  
Charlotte Sohier ◽  
Severine Matthijs ◽  
Nick De Regge
Keyword(s):  
Sex Ratio ◽  
Developmental Stages ◽  
Larval Mortality ◽  
Schmallenberg Virus ◽  
Food Sources ◽  
Economic Losses ◽  
Larval Food ◽  
Dark Light ◽  
Culicoides Obsoletus ◽  
Obsoletus Complex

During the last decade, Europe was confronted with the emergence of two Culicoides-borne viruses, bluetongue virus and Schmallenberg virus. Both diseases caused economic losses in cattle, sheep, and goats. Despite their importance, only limited knowledge is available on the developmental stages of Culicoides obsoletus complex midges, and a lab-reared colony has not yet been established. Therefore, this experimental study aims to compare the emergence patterns from field-collected C. obsoletus complex from egg to adult that were exposed to different combinations of temperature and larval substrates (T1: 1% liquid broth (LB) agar at 24 °C; T2: 1% LB agar with dung patches at 24 °C; T3: 1% LB agar at 28 °C). The rearing dishes were kept in an environmental chamber under an 8 h/16 h dark–light regime and 80%–85% humidity. Algae and nematodes were provided as a food source. The average period required to develop from egg to adult was 24 days and varied strongly in each of the conditions (T1: 15–47 days; T2: 14–35 days; T3: 20–37 days). A bias of sex ratio was observed towards the production of males in all three treatments with only 23.9% (T1), 23.5% (T2), and 0% (T3) females. Larval mortality was highest in T3 (25.9%), followed by T2 (8.6%), and T1 (1.8%). All pupae produced adults within 1 to 10 days, and the emergence rates for pupae varied strongly between treatments: 49.5% (T1), 71.6% (T2), and 38.5% (T3). This study shows that the C. obsoletus complex can be reared under laboratory conditions from blood-fed, wild-caught females to emerged progeny. More larval substrates and food sources should be tested with the aim of obtaining a 1:1 sex ratio to bring us one step closer to a viable lab-reared colony.

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