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Sample records for midge culicoides sonorensis

  1. The salivary secretome of the biting midge, Culicoides sonorensis

    PubMed Central

    Lehiy, Christopher J.

    2014-01-01

    Culicoides biting midges (Diptera: Ceratopogonidae) are hematophagous insects with over 1400 species distributed throughout the world. Many of these species are of particular agricultural importance as primary vectors of bluetongue and Schmallenberg viruses, yet little is known about Culicoides genomics and proteomics. Detailed studies of members from other blood-feeding Dipteran families, including those of mosquito (Culicidae) and black fly (Simuliidae), have shown that protein components within the insect’s saliva facilitate the blood feeding process. To determine the protein components in Culicoides sonorensis midges, secreted saliva was collected for peptide sequencing by tandem mass spectrometry. Forty-five secreted proteins were identified, including members of the D7 odorant binding protein family, Kunitz-like serine protease inhibitors, maltase, trypsin, and six novel proteins unique to C. sonorensis. Identifying the complex myriad of proteins in saliva from blood-feeding Dipteran species is critical for understanding their role in blood feeding, arbovirus transmission, and possibly the resulting disease pathogenesis. PMID:24949243

  2. Papular dermatitis induced in guinea pigs by the biting midge Culicoides sonorensis (Diptera: Ceratopogonidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Histological, ultrastructural, and virological examinations were performed on abdominal skin from guinea pigs after a blood meal by colony-bred biting midges, Culicoides sonorensis. Small, superficial, cutaneous, crateriform ulcers with necrosis of superficial dermis developed at feeding sites and ...

  3. Transcriptome analyses of blood and sugar digestive processes in female Culicoides sonorensis midges (Diptera: Ceratopogonidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Female Culicoides sonorensis Wirth & Jones (Diptera:Ceratopogonidae) midges vector numerous diseases impacting livestock and humans. The molecular physiology of this midge has been under-studied, so our approach was to gain an understanding of basic processes of blood and sucrose digestion using tra...

  4. Papular Dermatitis Induced in Guinea Pig by Biting Midge Culicoides Sonorensis (Diptera: Ceratopogonidaie)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Histological, ultrastructural, and virological examinations were performed on abdominal skin from guinea pigs after a blood meal by colony-bred biting midges, Culicoides sonorensis. Small, superficial, cutaneous, crateriform ulcers with necrosis of superficial dermis developed at feeding sites and h...

  5. Transmission of Vesicular Stomatitis New Jersey Virus to Cattle by the Biting Midge Culicoides sonorensis (Diptera: Ceratopogonidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interpretive Biting midges, Culicoides sonorensis were shown to transmit vesicular stomatitis virus serotype New Jersey (VSNJV) to four steers. Two other steers were exposed to VSNJV through intralingual inoculation. All six steers became seropositive for VSNJV. Only the animals intralingually inocu...

  6. The Biting Midge Culicoides sonorensis (Diptera: Ceratopogonidae) Is Capable of Developing Late Stage Infections of Leishmania enriettii

    PubMed Central

    Seblova, Veronika; Sadlova, Jovana; Vojtkova, Barbora; Votypka, Jan; Carpenter, Simon; Bates, Paul Andrew; Volf, Petr

    2015-01-01

    Background Despite their importance in animal and human health, the epidemiology of species of the Leishmania enriettii complex remains poorly understood, including the identity of their biological vectors. Biting midges of the genus Forcipomyia (Lasiohelea) have been implicated in the transmission of a member of the L. enriettii complex in Australia, but the far larger and more widespread genus Culicoides has not been investigated for the potential to include vectors to date. Methodology/Principal Findings Females from colonies of the midges Culicoides nubeculosus Meigen and C. sonorensis Wirth & Jones and the sand fly Lutzomyia longipalpis Lutz & Nevia (Diptera: Psychodidae) were experimentally infected with two different species of Leishmania, originating from Australia (Leishmania sp. AM-2004) and Brazil (Leishmania enriettii). In addition, the infectivity of L. enriettii infections generated in guinea pigs and golden hamsters for Lu. longipalpis and C. sonorensis was tested by xenodiagnosis. Development of L. enriettii in Lu. longipalpis was relatively poor compared to other Leishmania species in this permissive vector. Culicoides nubeculosus was not susceptible to infection by parasites from the L. enriettii complex. In contrast, C. sonorensis developed late stage infections with colonization of the thoracic midgut and the stomodeal valve. In hamsters, experimental infection with L. enriettii led only to mild symptoms, while in guinea pigs L. enriettii grew aggressively, producing large, ulcerated, tumour-like lesions. A high proportion of C. sonorensis (up to 80%) feeding on the ears and nose of these guinea pigs became infected. Conclusions/Significance We demonstrate that L. enriettii can develop late stage infections in the biting midge Culicoides sonorensis. This midge was found to be susceptible to L. enriettii to a similar degree as Lutzomyia longipalpis, the vector of Leishmania infantum in South America. Our results support the hypothesis that some

  7. Potential for Transovarial Transmission of Vesicular Stomatitis Virus in the biting midge, Culicoides sonorensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vesicular stomatitis virus (VSV) is an insect transmitted rhabdovirus which causes economically devastating disease in cattle and horses in the western U.S. Important insect vectors identified thus far include Lutzomyia shannoni sand flies, Simulium vittatum black flies, and Culicoides sonorensis bi...

  8. The Reference Transcriptome of the Adult Female Biting Midge (Culicoides sonorensis) and Differential Gene Expression Profiling during Teneral, Blood, and Sucrose Feeding Conditions

    PubMed Central

    Nayduch, Dana; Lee, Matthew B.; Saski, Christopher A.

    2014-01-01

    Unlike other important vectors such as mosquitoes and sandflies, genetic and genomic tools for Culicoides biting midges are lacking, despite the fact that they vector a large number of arboviruses and other pathogens impacting humans and domestic animals world-wide. In North America, female Culicoides sonorensis midges are important vectors of bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV), orbiviruses that cause significant disease in livestock and wildlife. Libraries of tissue-specific transcripts expressed in response to feeding and oral orbivirus challenge in C. sonorensis have previously been reported, but extensive genome-wide expression profiling in the midge has not. Here, we successfully used deep sequencing technologies to construct the first adult female C. sonorensis reference transcriptome, and utilized genome-wide expression profiling to elucidate the genetic response to blood and sucrose feeding over time. The adult female midge unigene consists of 19,041 genes, of which less than 7% are differentially expressed during the course of a sucrose meal, while up to 52% of the genes respond significantly in blood-fed midges, indicating hematophagy induces complex physiological processes. Many genes that were differentially expressed during blood feeding were associated with digestion (e.g. proteases, lipases), hematophagy (e.g., salivary proteins), and vitellogenesis, revealing many major metabolic and biological factors underlying these critical processes. Additionally, key genes in the vitellogenesis pathway were identified, which provides the first glimpse into the molecular basis of anautogeny for C. sonorensis. This is the first extensive transcriptome for this genus, which will serve as a framework for future expression studies, RNAi, and provide a rich dataset contributing to the ultimate goal of informing a reference genome assembly and annotation. Moreover, this study will serve as a foundation for subsequent studies of

  9. Seasonal and Interseasonal Dynamics of Bluetongue Virus Infection of Dairy Cattle and Culicoides sonorensis Midges in Northern California – Implications for Virus Overwintering in Temperate Zones

    PubMed Central

    Mayo, Christie E.; Mullens, Bradley A.; Reisen, William K.; Osborne, Cameron J.; Gibbs, E. Paul J.; Gardner, Ian A.; MacLachlan, N. James

    2014-01-01

    Bluetongue virus (BTV) is the cause of an economically important arboviral disease of domestic and wild ruminants. The occurrence of BTV infection of livestock is distinctly seasonal in temperate regions of the world, thus we determined the dynamics of BTV infection (using BTV-specific real time reverse transcriptase polymerase chain reaction) among sentinel cattle and vector Culicoides sonorensis (C. sonorensis) midges on a dairy farm in northern California throughout both the seasonal and interseasonal (overwintering) periods of BTV activity from August 2012 until March 2014. The data confirmed widespread infection of both sentinel cattle and vector midges during the August – November period of seasonal BTV transmission, however BTV infection of parous female midges captured in traps set during daylight hours also was detected in February of both 2013 and 2014, during the interseasonal period. The finding of BTV-infected vector midges during mid-winter suggests that BTV may overwinter in northern California by infection of long-lived female C. sonorensis midges that were infected during the prior seasonal period of virus transmission, and reemerged sporadically during the overwintering period; however the data do not definitively preclude other potential mechanisms of BTV overwintering that are also discussed. PMID:25215598

  10. Inducing RNA interference in the arbovirus vector, Culicoides sonorensis

    PubMed Central

    Mills, Mary K.; Nayduch, D.; Michel, K.

    2014-01-01

    Biting midges in the genus Culicoides are important vectors of arboviral diseases, including epizootic hemorrhagic disease, bluetongue, and likely Schmallenberg, which cause significant economic burden worldwide. Research on these vectors has been hindered by the lack of a sequenced genome, the difficulty of consistent culturing of certain species, and the absence of molecular techniques such as RNA interference (RNAi). Here, we report the establishment of RNAi as a research tool for the adult midge, Culicoides sonorensis. Based on previous research and transcriptome analysis, which revealed putative siRNA pathway member orthologs, we hypothesized that adult C. sonorensis midges have the molecular machinery needed to preform RNA silencing. Injection of control dsRNA, dsGFP, into the hemocoel 2–3 day old adult female midges resulted in survival curves that support virus transmission. DsRNA injection targeting the newly identified C. sonorensis inhibitor of apoptosis protein 1 (CsIAP1) ortholog, resulted in a 40% decrease of transcript levels and 73% shortened median survivals as compared to dsGFP-injected controls. These results reveal the conserved function of IAP1. Importantly, they also demonstrate the feasibility of RNAi by dsRNA injection in adult midges, which will greatly facilitate studies of the underlying mechanisms of vector competence in C. sonorensis. PMID:25293805

  11. Inducing RNA interference in the arbovirus vector, Culicoides sonorensis.

    PubMed

    Mills, M K; Nayduch, D; Michel, K

    2015-02-01

    Biting midges in the genus Culicoides are important vectors of arboviral diseases, including epizootic haemorrhagic disease, bluetongue and most likely Schmallenberg, which cause significant economic burdens worldwide. Research on these vectors has been hindered by the lack of a sequenced genome, the difficulty of consistent culturing of certain species and the absence of molecular techniques such as RNA interference (RNAi). Here, we report the establishment of RNAi as a research tool for the adult midge, Culicoides sonorensis. Based on previous research and transcriptome analysis, which revealed putative small interfering RNA pathway member orthologues, we hypothesized that adult C. sonorensis midges have the molecular machinery needed to perform RNA silencing. Injection of control double-stranded RNA targeting green fluorescent protein (dsGFP), into the haemocoel of 2-3-day-old adult female midges resulted in survival curves that support virus transmission. dsRNA injection targeting the newly identified C. sonorensis inhibitor of apoptosis protein 1 (CsIAP1) orthologue resulted in a 40% decrease of transcript levels and 73% shorter median survivals as compared with dsGFP-injected controls. These results reveal the conserved function of IAP1. Importantly, they also demonstrate the feasibility of RNAi by dsRNA injection in adult midges, which will greatly facilitate studies of the underlying mechanisms of vector competence in C. sonorensis. PMID:25293805

  12. Salivary gland extracts of Culicoides sonorensis inhibit murine lymphocyte proliferation and no production by macrophages.

    PubMed

    Bishop, Jeanette V; Mejia, J Santiago; Pérez de León, Adalberto A; Tabachnick, Walter J; Titus, Richard G

    2006-09-01

    Culicoides biting midges serve as vectors of pathogens affecting humans and domestic animals. Culicoides sonorensis is a vector of several arboviruses in North American that cause substantial economic losses to the US livestock industry. Previous studies showed that C. sonorensis saliva, like the saliva of many hematophagous arthropods, contains numerous pharmacological agents that affect hemostasis and early events in the inflammatory response, which may enhance the infectivity of Culicoides-borne pathogens. This paper reports on the immunomodulatory properties of C. sonorensis salivary gland extracts on murine immune cells and discusses the possible immunomodulatory role of C. sonorensis saliva in vesicular stomatitis virus infection of vertebrate hosts. Splenocytes treated with C. sonorensis mitogens were significantly affected in their proliferative response, and peritoneal macrophages secreted significantly less NO. A 66-kDa glycoprotein was purified from C. sonorensis salivary gland extract, which may be in part responsible for these observations and may be considered as a vaccine candidate. PMID:16968936

  13. Gene discovery and differential expression analysis of humoral immune response elements in female Culicoides sonorensis (Diptera: Ceratopogonidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Female Culicoides sonorensis midges (Diptera: Ceratopogonidae) are vectors of pathogens that impact livestock and wildlife in the United States. Little is known about their molecular functioning, including components of their immune system. Because the insect immune response is involved ...

  14. Effects of Viral Infection on Blood-Feeding Behavior in Culicoides sonorensis (Diptera: Ceratopogonidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Culicoides sonorensis (Diptera: Ceratopogonidae) is the primary vector of bluetongue virus (BTV) in North America and a competent vector of vesicular stomatitis virus (VSV). Little is known about how viral infection of this midge affects its blood feeding behavior. Midges were intrathoracically inoc...

  15. The reference transcriptome of the adult female biting midge (Culicoides sonorensis) and differential gene expression profiling during teneral, blood, and sucrose feeding conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unlike other important vectors such as mosquitoes and sandflies, genetic and genomic tools for Culicoides biting midges are lacking, despite the fact that they vector a large number of arboviruses and other pathogens impacting humans and domestic animals world-wide. In North America, female Culicoid...

  16. Identification, expression, and characterization of a major salivary allergen (Cul s 1) of the biting midge Culicoides sonorensis relevant for summer eczema in horses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salivary proteins of Culicoides biting midges are thought to play a key role in the induction of summer eczema (SE), a seasonal recurrent allergic dermatitis in horses. The present study describes the identification of a candidate allergen in artificially collected saliva of the North American speci...

  17. Trap placement and attractant choice affect capture and create sex and parity biases in collections of the biting midge, Culicoides sonorensis.

    PubMed

    McDermott, E G; Mayo, C E; Gerry, A C; Mullens, B A

    2016-09-01

    Culicoides sonorensis Wirth & Jones (Diptera: Ceratopogonidae) is the primary North American vector of bluetongue virus (BTV), which can cause high morbidity and mortality in ruminant livestock or wildlife. Worldwide, most Culicoides surveillance relies on light (usually UV) traps typically placed near animals or larval development sites. However, the trapping method can cause sex, species and parity biases in collections. We collected C. sonorensis from three dairies in California using suction traps baited with CO2 , UV light or CO2  + UV placed near animals, wastewater ponds, or in fields. Higher numbers of parous females were collected using CO2  + UV traps, although this difference was only significant on one dairy. UV traps were poor at collecting nulliparous females, but the addition of UV to a trap increased the abundance of males in a collection. Traps set in open fields collected significantly higher numbers of males and females than in either of the other two locations. In some cases, there was a significant interaction between the trap type and site. We discuss the limitations of traditional trapping methodologies for C. sonorensis and make suggestions for vector surveillance. PMID:27257164

  18. Blood Feeding Behavior of Vesicular Stomatitis Virus Infected Culicoides Sonorensis (Diptera: Ceratopogonidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Culicoides sonorensis (Diptera: Ceratopogonidae) is the primary vector of Bluetongue virus in North America and a competent vector of Vesicular Stomatitis virus (VSV). Little is known about how viral infection of this midge affects blood feeding behavior and how this might affect virus transmission....

  19. Effects of Viral Infection on Blood Feeding Behavior and Fecundity in Culicoides Sonorensis (Diptera: Ceratopogonidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Culicoides sonorensis (Diptera: Ceratopogonidae) is the primary vector of bluetongue virus (BTV) in North America and a competent vector of vesicular stomatitis virus (VSV). Little is known about how viral infection of this midge affects its blood feeding behavior and fecundity. Blood feeding succes...

  20. Infection of Guinea Pigs with Vesicular Stomatitis New Jersey Virus Transmitted by Culicoides sonorensis (Diptera: Ceratopogonidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interpretive Biting midges,Culicoides sonorensis were shown to be capable of transmitting vesicular stomatitis New Jersey virus (VSNJV) to guinea pigs. Despite seroconversion for VSNJV, none of the guinea pigs developed clinical signs when infected in the abdomen by either infected insects or by nee...

  1. Impact of the blood meal on humoral immunity and microbiota in the gut of female Culicoides sonorensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although Culicoides sonorensis is an important vector of orbiviruses that cause significant disease in domestic and wild ruminants in the USA, little is known about factors contributing to midge vector competence. In other vectors such as mosquitoes, interactions between the humoral immune response,...

  2. Vector competence of Culicoides sonorensis (Diptera: Ceratopogonidae) to epizootic hemorrhagic disease virus serotype 7

    PubMed Central

    2012-01-01

    Background Culicoides sonorensis (Diptera: Ceratopogonidae) is a vector of epizootic hemorrhagic disease virus (EHDV) serotypes 1 and 2 in North America, where these viruses are well-known pathogens of white-tailed deer (WTD) and other wild ruminants. Although historically rare, reports of clinical EHDV infection in cattle have increased in some parts of the world over the past decade. In 2006, an EHDV-7 epizootic in cattle resulted in economic loss for the Israeli dairy industry. White-tailed deer are susceptible to EHDV-7 infection and disease; however, this serotype is exotic to the US and the susceptibility of C. sonorensis to this cattle-virulent EHDV is not known. The objective of the study was to determine if C. sonorensis is susceptible to EHDV-7 infection and is a competent vector. Methods To evaluate the susceptibility of C. sonorensis, midges were fed on EHDV-7 infected WTD, held at 22 ± 1°C, and processed individually for virus isolation and titration on 4–16 days post feeding (dpf). Midges with a virus titer of ≥102.7 median tissue culture infective doses (TCID50)/midge were considered potentially competent. To determine if infected C. sonorensis were capable of transmitting EHDV-7 to a host, a susceptible WTD was then fed on by a group of 14–16 dpf midges. Results From 4–16 dpf, 45% (156/350) of midges that fed on WTD with high titer viremia (>107 TCID50/ml) were virus isolation-positive, and starting from 10–16 dpf, 32% (35/109) of these virus isolation-positive midges were potentially competent (≥102.7 TCID50/midge). Midges that fed on infected deer transmitted the virus to a susceptible WTD at 14–16 dpf. The WTD developed viremia and severe clinical disease. Conclusion This study demonstrates that C. sonorensis is susceptible to EHDV-7 infection and can transmit the virus to susceptible WTD, thus, C. sonorensis should be considered a potential vector of EHDV-7. Together with previous work, this study demonstrates that North America

  3. Distribution (presence / absence) of Culicoides Sonorensis (Diptera: Ceratopogonidae) in Nebraska, South Dakota, and North Dakota: Clarifying the Epidemiology of Bluetongue Disease in the North-Central United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The presence or absence of the biting midge, Culicoides sonorensis, a primary vector of bluetongue viruses (BTV) in North America, was assessed on ranches and farms across the north-central region of the United States (U.S.), specifically the states of Nebraska, South Dakota, and North Dakota, as pa...

  4. Effect of Temperature on Replication of Epizootic Hemorrhagic Disease Viruses in Culicoides sonorensis (Diptera: Ceratopogonidae).

    PubMed

    Ruder, Mark G; Stallknecht, David E; Howerth, Elizabeth W; Carter, Deborah L; Pfannenstiel, Robert S; Allison, Andrew B; Mead, Daniel G

    2015-09-01

    Replication of arboviruses, including orbiviruses, within the vector has been shown to be temperature dependent. Cooler ambient temperatures slow virus replication in arthropod vectors, whereas viruses replicate faster and to higher titers at warmer ambient temperatures. Previous research with epizootic hemorrhagic disease virus (EHDV) serotype 1 demonstrated that higher temperatures were associated with shorter extrinsic incubation periods in Culicoides sonorensis Wirth & Jones, a confirmed vector of EHDV in North America. To further our understanding of the effect of temperature on replication of EHDV within the vector, C. sonorensis were experimentally infected with one of three EHDV strains representing three serotypes (1, 2, and 7). Midges were fed defibrinated white-tailed deer (Odocoileus virginianus) blood spiked with EHDV (≥10(6.5) TCID(50)/ml) through a parafilm membrane using an artificial feeding device and were then held at 20, 25, or 30°C. In addition to this in vitro method, a white-tailed deer experimentally infected with EHDV-7 was used to provide an infectious bloodmeal to determine if the results were comparable with those from the in vitro feeding method. Whole midges were processed for virus isolation and titration at regular intervals following feeding; midges with ≥10(2.7) TCID(50) were considered potentially competent to transmit virus. The virus recovery rates were high throughout the study and all three viruses replicated within C. sonorensis to high titer (≥ 10(2.7) TCID(50)/midge). Across all virus strains, the time to detection of potentially competent midges decreased with increasing temperature: 12-16 d postfeeding (dpf) at 20°C, 4-6 dpf at 25°C, and 2-4 dpf at 30°C. Significant differences in replication of the three viruses in C. sonorensis were observed, with EHDV-2 replicating to a high titer in a smaller proportion of midges and with lower peak titers. The findings are consistent with previous studies of related

  5. Management of North American Culicoides Biting Midges: Current Knowledge and Research Needs.

    PubMed

    Pfannenstiel, Robert S; Mullens, Bradley A; Ruder, Mark G; Zurek, Ludek; Cohnstaedt, Lee W; Nayduch, Dana

    2015-06-01

    Culicoides biting midges (Diptera: Ceratopogonidae) are biological vectors of two important viruses impacting North American ruminants--bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV). These viruses have been identified for over 60 years in North America, but we still lack an adequate understanding of the basic biology and ecology of the confirmed vector, Culicoides sonorensis, and know even less about other putative Culicoides vector species. The major gaps in our knowledge of the biology of Culicoides midges are broad and include an understanding of the ecology of juveniles, the identity of potential alternate vector species, interactions of midges with both pathogens and vertebrates, and the effectiveness of potential control measures. Due to these broad and numerous fundamental knowledge gaps, vector biologists and livestock producers are left with few options to respond to or understand outbreaks of EHD or BT in North America, or respond to emerging or exotic Culicoides-transmitted pathogens. Here we outline current knowledge of vector ecology and control tactics for North American Culicoides species, and delineate research recommendations aimed to fill knowledge gaps. PMID:26086558

  6. Lack of Evidence for Laboratory and Natural Vertical Transmission of Bluetongue Virus in Culicoides sonorensis (Diptera: Ceratopogonidae)

    PubMed Central

    Mayo, C. E.; Mullens, B. A.; McDermott, E. G.; Gerry, A. C.; Reisen, W. K.; MacLachlan, N. J.

    2015-01-01

    Culicoides sonorensis (Wirth & Jones) is the principal North American vector of bluetongue virus (BTV). BTV infection of livestock is distinctly seasonal (late summer and fall) in temperate regions of the world such as California, which has led to speculation regarding vertical transmission of the virus within the midge vector as a potential mechanism for interseasonal maintenance (“overwintering”) of the virus. To evaluate potential vertical transmission of BTV in its midge vector, we fed adult midges BTV-spiked blood and used a BTV-specific quantitative reverse transcriptase polymerase chain reaction assay to evaluate parent, egg, and progeny stages of laboratory-reared C. sonorensis for the presence of viral nucleic acid. Whereas BTV nucleic acid was weakly detected in egg batches of virus-fed female midges, virus was never detected in subsequent progeny stages (larvae, pupae, and F1 generation adults). Similarly, BTV was not detected in pools of larvae collected from the waste-water lagoon of a BTV-endemic dairy farm in northern California during the seasonal period of virus transmission. Collectively, these results indicate that BTV is not readily transmitted vertically in C. sonorensis, and that persistence of the virus in long-lived parous female midges is a more likely mechanism for overwintering of BTV in temperate regions. PMID:26336312

  7. Lack of Evidence for Laboratory and Natural Vertical Transmission of Bluetongue Virus in Culicoides sonorensis (Diptera: Ceratopogonidae).

    PubMed

    Osborne, C J; Mayo, C E; Mullens, B A; McDermott, E G; Gerry, A C; Reisen, W K; MacLachlan, N J

    2015-03-01

    Culicoides sonorensis (Wirth & Jones) is the principal North American vector of bluetongue virus (BTV). BTV infection of livestock is distinctly seasonal (late summer and fall) in temperate regions of the world such as California, which has led to speculation regarding vertical transmission of the virus within the midge vector as a potential mechanism for interseasonal maintenance ("overwintering") of the virus. To evaluate potential vertical transmission of BTV in its midge vector, we fed adult midges BTV-spiked blood and used a BTV-specific quantitative reverse transcriptase polymerase chain reaction assay to evaluate parent, egg, and progeny stages of laboratory-reared C. sonorensis for the presence of viral nucleic acid. Whereas BTV nucleic acid was weakly detected in egg batches of virus-fed female midges, virus was never detected in subsequent progeny stages (larvae, pupae, and F1 generation adults). Similarly, BTV was not detected in pools of larvae collected from the waste-water lagoon of a BTV-endemic dairy farm in northern California during the seasonal period of virus transmission. Collectively, these results indicate that BTV is not readily transmitted vertically in C. sonorensis, and that persistence of the virus in long-lived parous female midges is a more likely mechanism for overwintering of BTV in temperate regions. PMID:26336312

  8. Inducing RNA interference in the arbovirus vector, Culicoides sonorensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biting midges in the genus Culicoides are important vectors of arboviral diseases, including Epizootic Hemorrhagic Disease, Bluetongue, and likely Schmallenberg, which cause significant economic burden worldwide. Research on these vectors has been hindered by the lack of a sequenced genome, the diff...

  9. Control of Culicoides sonorensis (Diptera: Ceratopogonidae) blood feeding on sheep with long-lasting repellent pesticides.

    PubMed

    Reeves, W K; Lloyd, J E; Stobart, R; Stith, C; Miller, M M; Bennett, K E; Johnson, G

    2010-09-01

    Culicoides sonorensis is the primary vector of bluetongue and epizootic hemorrhagic disease viruses in North America. Bluetongue disease is one of the most economically important arthropod-borne diseases of sheep in North America, because it causes significant morbidity and mortality and can lead to local quarantines and international trade restrictions. Long-lasting repellent pesticides could be applied to sheep as they are moved down from mountain pastures to protect them from biting midges until the 1st frost. We tested long-lasting pesticides on sheep as repellents against C. sonorensis. Both Python ear tags with 10% zeta-cypermethrin (9.8 g/tag) synergized with 20% piperonyl butoxide (PBO) and a 12-ml low-volume spray application of ready-to-use sheep insecticide (Y-TEX) with 2.5% permethrin and 2.5% PBO in an oil-based formulation were repellent to C. sonorensis for at least 3-5 wk after a single application. PMID:21033057

  10. Behavior of larval Culicoides Sonorensis (Diptera: Ceratopogonidae) in response to an invertebrate predator, Hydra Littoralis (Anthomedusae: Hydridae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Larvae of Culicoides sonorensis a blood feeding ceratopogonid are aquatic. In their natural habitat they are exposed to numerous predators. Predator avoidance behavior has not been studied in most Culicoides spp. Based on laboratory data the larvae of Culicoides sonorensis behave differently when cn...

  11. Biting midges of the genus Culicoides in South Carolina zoos.

    PubMed

    Nelder, Mark P; Swanson, Dustin A; Adler, Peter H; Grogan, William L

    2010-01-01

    Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) were collected during the summer of 2007 at the Greenville and Riverbanks Zoos in South Carolina with Centers for Disease Control and Prevention (CDC) traps equipped with ultraviolet or incandescent lights and baited with carbon dioxide. Sixteen species of Culicoides were collected, four of which represented more than 80%. They were Culicoides guttipennis (Coquillett), Culicoides mulrenanni Beck, Culicoides obsoletus (Meigen), and Culicoides sanguisuga (Coquillett). C. guttipennis was found on a dead colobus monkey and a dead golden-headed lion tamarin; Culicoides husseyi Wirth & Blanton was collected from an unidentified, abandoned bird's nest. Ultraviolet light-equipped traps captured significantly more Culicoides specimens than traps with incandescent light. Half of the collected species previously have been associated with vertebrate pathogens, indicating a potential risk to captive animals. PMID:20569132

  12. Biting Midges of the Genus Culicoides in South Carolina Zoos

    PubMed Central

    Nelder, Mark P.; Swanson, Dustin A.; Adler, Peter H.; Grogan, William L.

    2010-01-01

    Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) were collected during the summer of 2007 at the Greenville and Riverbanks Zoos in South Carolina with Centers for Disease Control and Prevention (CDC) traps equipped with ultraviolet or incandescent lights and baited with carbon dioxide. Sixteen species of Culicoides were collected, four of which represented more than 80%. They were Culicoides guttipennis (Coquillett), Culicoides mulrenanni Beck, Culicoides obsoletus (Meigen), and Culicoides sanguisuga (Coquillett). C. guttipennis was found on a dead colobus monkey and a dead golden-headed lion tamarin; Culicoides husseyi Wirth & Blanton was collected from an unidentified, abandoned bird's nest. Ultraviolet light-equipped traps captured significantly more Culicoides specimens than traps with incandescent light. Half of the collected species previously have been associated with vertebrate pathogens, indicating a potential risk to captive animals. PMID:20569132

  13. Schmallenberg Virus Circulation in Culicoides in Belgium in 2012: Field Validation of a Real Time RT-PCR Approach to Assess Virus Replication and Dissemination in Midges

    PubMed Central

    De Regge, Nick; Madder, Maxime; Deblauwe, Isra; Losson, Bertrand; Fassotte, Christiane; Demeulemeester, Julie; Smeets, François; Tomme, Marie; Cay, Ann Brigitte

    2014-01-01

    Indigenous Culicoides biting midges are suggested to be putative vectors for the recently emerged Schmallenberg virus (SBV) based on SBV RNA detection in field-caught midges. Furthermore, SBV replication and dissemination has been evidenced in C. sonorensis under laboratory conditions. After SBV had been detected in Culicoides biting midges from Belgium in August 2011, it spread all over the country by the end of 2011, as evidenced by very high between-herd seroprevalence rates in sheep and cattle. This study investigated if a renewed SBV circulation in midges occurred in 2012 in the context of high seroprevalence in the animal host population and evaluated if a recently proposed realtime RT-PCR approach that is meant to allow assessing the vector competence of Culicoides for SBV and bluetongue virus under laboratory conditions was applicable to field-caught midges. Therefore midges caught with 12 OVI traps in four different regions in Belgium between May and November 2012, were morphologically identified, age graded, pooled and tested for the presence of SBV RNA by realtime RT-PCR. The results demonstrate that although no SBV could be detected in nulliparous midges caught in May 2012, a renewed but short lived circulation of SBV in parous midges belonging to the subgenus Avaritia occured in August 2012 at all four regions. The infection prevalence reached up to 2.86% in the south of Belgium, the region where a lower seroprevalence was found at the end of 2011 than in the rest of the country. Furthermore, a frequency analysis of the Ct values obtained for 31 SBV-S segment positive pools of Avaritia midges showed a clear bimodal distribution with peaks of Ct values between 21–24 and 33–36. This closely resembles the laboratory results obtained for SBV infection of C. sonorensis and implicates indigenous midges belonging to the subgenus Avaritia as competent vectors for SBV. PMID:24466312

  14. Control of Culicoides Sonorensis (Diptera: Ceratopogonidae)blood feeding on sheep with long lasting repellent pesticides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Culicoides sonorensis is the primary vector of bluetongue and epizootic hemorrhagic disease viruses in North America. Bluetongue disease is considered one of the most economically important arthropod-borne diseases of sheep in North America because it causes significant morbidity and mortality and ...

  15. Effects of Melezitose and Stachyose on Adult Longevity and Virus Persistence in Culicoides Sonorensis (Diptera: Ceratopogonidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A wide variety of blood feeding Diptera feed on extrafloral sugar sources such as homopteran honeydew. he significance of these sugar sources to insect survival and disease transmission are poorly known. Culicoides sonorensis can survive on plant sugars but might feed on homopteran honeydew. The su...

  16. Vector competence of Culicoides sonorensis (Diptera: Ceratopogonidae) to epizootic hemorrhagic disease virus serotype 7

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Culicoides sonorensis (Diptera: Ceratopogonidae) is a vector of epizootic hemorrhagic disease virus (EHDV) serotypes 1 and 2 in North America, where these viruses are well-known pathogens of white-tailed deer (WTD) and other wild ruminants. Although historically rare, reports of clinica...

  17. Susceptibility of Culicoides sonorensis to infection with EHDV-6 (Indiana) and comparison to EHDV-1 and -2

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Epizootic hemorrhagic disease virus (EHDV) serotypes 1 and 2 are endemic to North America. Although Culicoides sonorensis is considered to be the primary vector, outbreaks have occurred in regions of the US where C. sonorensis are not typically found. In 2006, EHDV-6, a serotype not previously doc...

  18. Measurement of the Infection and Dissemination of Bluetongue Virus in Culicoides Biting Midges Using a Semi-Quantitative RT-PCR Assay and Isolation of Infectious Virus

    PubMed Central

    Veronesi, Eva; Antony, Frank; Gubbins, Simon; Golding, Nick; Blackwell, Alison; Mertens, Peter PC.; Brownlie, Joe; Darpel, Karin E.; Mellor, Philip S.; Carpenter, Simon

    2013-01-01

    Background Culicoides biting midges (Diptera: Ceratopogonidae) are the biological vectors of globally significant arboviruses of livestock including bluetongue virus (BTV), African horse sickness virus (AHSV) and the recently emerging Schmallenberg virus (SBV). From 2006–2009 outbreaks of BTV in northern Europe inflicted major disruption and economic losses to farmers and several attempts were made to implicate Palaearctic Culicoides species as vectors. Results from these studies were difficult to interpret as they used semi-quantitative RT-PCR (sqPCR) assays as the major diagnostic tool, a technique that had not been validated for use in this role. In this study we validate the use of these assays by carrying out time-series detection of BTV RNA in two colony species of Culicoides and compare the results with the more traditional isolation of infectious BTV on cell culture. Methodology/Principal Findings A BTV serotype 1 strain mixed with horse blood was fed to several hundred individuals of Culicoides sonorensis (Wirth & Jones) and C. nubeculosus (Mg.) using a membrane-based assay and replete individuals were then incubated at 25°C. At daily intervals 25 Culicoides of each species were removed from incubation, homogenised and BTV quantified in each individual using sqPCR (Cq values) and virus isolation on a KC-C. sonorensis embryonic cell line, followed by antigen enzyme-linked immunosorbent assay (ELISA). In addition, comparisons were also drawn between the results obtained with whole C. sonorensis and with individually dissected individuals to determine the level of BTV dissemination. Conclusions/Significance Cq values generated from time-series infection experiments in both C. sonorensis and C. nubeculosus confirmed previous studies that relied upon the isolation and detection of infectious BTV. Implications on the testing of field-collected Culicoides as potential virus vectors by PCR assays and the use of such assays as front-line tools for use in

  19. Modelling the Northward Expansion of Culicoides sonorensis (Diptera: Ceratopogonidae) under Future Climate Scenarios

    PubMed Central

    Lysyk, Timothy; Johnson, Gregory; Marshall, Shawn; Berger, Kathryn; Cork, Susan Catherine

    2015-01-01

    Climate change is affecting the distribution of pathogens and their arthropod vectors worldwide, particularly at northern latitudes. The distribution of Culicoides sonorensis (Diptera: Ceratopogonidae) plays a key role in affecting the emergence and spread of significant vector borne diseases such as Bluetongue (BT) and Epizootic Hemorrhagic Disease (EHD) at the border between USA and Canada. We used 50 presence points for C. sonorensis collected in Montana (USA) and south-central Alberta (Canada) between 2002 and 2012, together with monthly climatic and environmental predictors to develop a series of alternative maximum entropy distribution models. The best distribution model under current climatic conditions was selected through the Akaike Information Criterion, and included four predictors: Vapour Pressure Deficit of July, standard deviation of Elevation, Land Cover and mean Precipitation of May. This model was then projected into three climate change scenarios adopted by the IPCC in its 5th assessment report and defined as Representative Concentration Pathways (RCP) 2.6, 4.5 and 8.5. Climate change data for each predictor and each RCP were calculated for two time points pooling decadal data around each one of them: 2030 (2021–2040) and 2050 (2041–2060). Our projections showed that the areas predicted to be at moderate-high probability of C. sonorensis occurrence would increase from the baseline scenario to 2030 and from 2030 to 2050 for each RCP. The projection also indicated that the current northern limit of C. sonorensis distribution is expected to move northwards to above 53°N. This may indicate an increased risk of Culicoides-borne diseases occurrence over the next decades, particularly at the USA-Canada border, as a result of changes which favor C. sonorensis presence when associated to other factors (i.e. host and pathogen factors). Recent observations of EHD outbreaks in northern Montana and southern Alberta supported our projections and

  20. Modelling the Northward Expansion of Culicoides sonorensis (Diptera: Ceratopogonidae) under Future Climate Scenarios.

    PubMed

    Zuliani, Anna; Massolo, Alessandro; Lysyk, Timothy; Johnson, Gregory; Marshall, Shawn; Berger, Kathryn; Cork, Susan Catherine

    2015-01-01

    Climate change is affecting the distribution of pathogens and their arthropod vectors worldwide, particularly at northern latitudes. The distribution of Culicoides sonorensis (Diptera: Ceratopogonidae) plays a key role in affecting the emergence and spread of significant vector borne diseases such as Bluetongue (BT) and Epizootic Hemorrhagic Disease (EHD) at the border between USA and Canada. We used 50 presence points for C. sonorensis collected in Montana (USA) and south-central Alberta (Canada) between 2002 and 2012, together with monthly climatic and environmental predictors to develop a series of alternative maximum entropy distribution models. The best distribution model under current climatic conditions was selected through the Akaike Information Criterion, and included four predictors: Vapour Pressure Deficit of July, standard deviation of Elevation, Land Cover and mean Precipitation of May. This model was then projected into three climate change scenarios adopted by the IPCC in its 5th assessment report and defined as Representative Concentration Pathways (RCP) 2.6, 4.5 and 8.5. Climate change data for each predictor and each RCP were calculated for two time points pooling decadal data around each one of them: 2030 (2021-2040) and 2050 (2041-2060). Our projections showed that the areas predicted to be at moderate-high probability of C. sonorensis occurrence would increase from the baseline scenario to 2030 and from 2030 to 2050 for each RCP. The projection also indicated that the current northern limit of C. sonorensis distribution is expected to move northwards to above 53°N. This may indicate an increased risk of Culicoides-borne diseases occurrence over the next decades, particularly at the USA-Canada border, as a result of changes which favor C. sonorensis presence when associated to other factors (i.e. host and pathogen factors). Recent observations of EHD outbreaks in northern Montana and southern Alberta supported our projections and considerations

  1. Repellent pesticides for the control of Culicoides sonorensis on sheep

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bluetongue disease is a sporadic and unpredictable disease in the northern Rocky Mountains. Epizootics can be separated by decades of little to no disease activity. Woolgrowers need access to control technologies that can be used after an outbreak is detected. We tested 6 formulations of midge repel...

  2. Bionomics of temperate and tropical Culicoides midges: knowledge gaps and consequences for transmission of Culicoides-borne viruses.

    PubMed

    Purse, B V; Carpenter, S; Venter, G J; Bellis, G; Mullens, B A

    2015-01-01

    Culicoides midges are abundant hematophagous flies that vector arboviruses of veterinary and medical importance. Dramatic changes in the epidemiology of Culicoides-borne arboviruses have occurred since 1998, including the emergence of exotic viruses in northern temperate regions, increases in global disease incidence, and enhanced virus diversity in tropical zones. Drivers may include changes in climate, land use, trade, and animal husbandry. New Culicoides species and new wild reservoir hosts have been implicated in transmission, highlighting the dynamic nature of pathogen-vector-host interactions. Focusing on potential vector species worldwide and key elements of vectorial capacity, we review the sensitivity of Culicoides life cycles to abiotic and biotic factors. We consider implications for designing control measures and understanding impacts of environmental change in different ecological contexts. Critical geographical, biological, and taxonomic knowledge gaps are prioritized. Recent developments in genomics and mathematical modeling may enhance ecological understanding of these complex arbovirus systems. PMID:25386725

  3. Identity and diversity of blood meal hosts of biting midges (Diptera: Ceratopogonidae: Culicoides Latreille) in Denmark

    PubMed Central

    2012-01-01

    Background Host preference studies in haematophagous insects e.g. Culicoides biting midges are pivotal to assess transmission routes of vector-borne diseases and critical for the development of veterinary contingency plans to identify which species should be included due to their risk potential. Species of Culicoides have been found in almost all parts of the world and known to live in a variety of habitats. Several parasites and viruses are transmitted by Culicoides biting midges including Bluetongue virus and Schmallenberg virus. The aim of the present study was to determine the identity and diversity of blood meals taken from vertebrate hosts in wild-caught Culicoides biting midges near livestock farms. Methods Biting midges were collected at weekly intervals for 20 weeks from May to October 2009 using light traps at four collection sites on the island Sealand, Denmark. Blood-fed female biting midges were sorted and head and wings were removed for morphological species identification. The thoraxes and abdomens including the blood meals of the individual females were subsequently subjected to DNA isolation. The molecular marker cytochrome oxidase I (COI barcode) was applied to identify the species of the collected biting midges (GenBank accessions JQ683259-JQ683374). The blood meals were first screened with a species-specific cytochrome b primer pair for cow and if negative with a universal cytochrome b primer pair followed by sequencing to identify mammal or avian blood meal hosts. Results Twenty-four species of biting midges were identified from the four study sites. A total of 111,356 Culicoides biting midges were collected, of which 2,164 were blood-fed. Specimens of twenty species were identified with blood in their abdomens. Blood meal sources were successfully identified by DNA sequencing from 242 (76%) out of 320 Culicoides specimens. Eight species of mammals and seven species of birds were identified as blood meal hosts. The most common host species was

  4. Insecticidal sugar baits for adult biting midges

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the latest trends in mosquito control is the use of insecticidal sugar baits (ISBs) to reduce adult mosquito populations. Tested here is the ability of ISB’s to knock-down the biting midge, Culicoides sonorensis, a disease vector of bluetongue, epizootic hemorrhagic disease, and vesicular sto...

  5. Abundance of biting midge species (Diptera: Ceratopogonidae, Culicoides spp.) on cattle farms in Korea

    PubMed Central

    Oem, Jae-Ku; Chung, Joon-Yee; Kwon, Mee-Soon; Kim, Toh-Kyung; Lee, Tae-Uk

    2013-01-01

    Culicoides biting midges were collected on three cattle farms weekly using light traps overnight from May to October between 2010 and 2011 in the southern part of Korea. The seasonal and geographical abundance of Culicodes spp. were measured. A total of 16,538 biting midges were collected from 2010 to 2011, including seven species of Culicoides, four of which represented 98.42% of the collected specimens. These four species were Culicodes (C.) punctatus (n = 14,413), C. arakawae (n = 1,120), C. oxystoma (n = 427), and C. maculatus (n = 318). C. punctatus was the predominant species (87.15%). PMID:23388441

  6. Seasonal Variation and Impact of Waste-Water Lagoons as Larval Habitat on the Population Dynamics of Culicoides sonorensis (Diptera:Ceratpogonidae) at Two Dairy Farms in Northern California

    PubMed Central

    Mayo, Christie E.; Osborne, Cameron J.; Mullens, Bradley A.; Gerry, Alec C.; Gardner, Ian A.; Reisen, William K.; Barker, Christopher M.; MacLachlan, N. James

    2014-01-01

    The Sacramento (northern Central) Valley of California (CA) has a hot Mediterranean climate and a diverse ecological landscape that is impacted extensively by human activities, which include the intensive farming of crops and livestock. Waste-water ponds, marshes, and irrigated fields associated with these agricultural activities provide abundant larval habitats for C. sonorensis midges, in addition to those sites that exist in the natural environment. Within this region, C. sonorensis is an important vector of bluetongue (BTV) and related viruses that adversely affect the international trade and movement of livestock, the economics of livestock production, and animal welfare. To characterize the seasonal dynamics of immature and adult C. sonorensis populations, abundance was monitored intensively on two dairy farms in the Sacramento Valley from August 2012– to July 2013. Adults were sampled every two weeks for 52 weeks by trapping (CDC style traps without light and baited with dry-ice) along N-S and E-W transects on each farm. One farm had large operational waste-water lagoons, whereas the lagoon on the other farm was drained and remained dry during the study. Spring emergence and seasonal abundance of adult C. sonorensis on both farms coincided with rising vernal temperature. Paradoxically, the abundance of midges on the farm without a functioning waste-water lagoon was increased as compared to abundance on the farm with a waste-water lagoon system, indicating that this infrastructure may not serve as the sole, or even the primary larval habitat. Adult midges disappeared from both farms from late November until May; however, low numbers of parous female midges were detected in traps set during daylight in the inter-seasonal winter period. This latter finding is especially critical as it provides a potential mechanism for the “overwintering” of BTV in temperate regions such as northern CA. Precise documentation of temporal changes in the annual abundance and

  7. Seasonal variation and impact of waste-water lagoons as larval habitat on the population dynamics of Culicoides sonorensis (Diptera:Ceratpogonidae) at two dairy farms in northern California.

    PubMed

    Mayo, Christie E; Osborne, Cameron J; Mullens, Bradley A; Gerry, Alec C; Gardner, Ian A; Reisen, William K; Barker, Christopher M; Maclachlan, N James

    2014-01-01

    The Sacramento (northern Central) Valley of California (CA) has a hot Mediterranean climate and a diverse ecological landscape that is impacted extensively by human activities, which include the intensive farming of crops and livestock. Waste-water ponds, marshes, and irrigated fields associated with these agricultural activities provide abundant larval habitats for C. sonorensis midges, in addition to those sites that exist in the natural environment. Within this region, C. sonorensis is an important vector of bluetongue (BTV) and related viruses that adversely affect the international trade and movement of livestock, the economics of livestock production, and animal welfare. To characterize the seasonal dynamics of immature and adult C. sonorensis populations, abundance was monitored intensively on two dairy farms in the Sacramento Valley from August 2012- to July 2013. Adults were sampled every two weeks for 52 weeks by trapping (CDC style traps without light and baited with dry-ice) along N-S and E-W transects on each farm. One farm had large operational waste-water lagoons, whereas the lagoon on the other farm was drained and remained dry during the study. Spring emergence and seasonal abundance of adult C. sonorensis on both farms coincided with rising vernal temperature. Paradoxically, the abundance of midges on the farm without a functioning waste-water lagoon was increased as compared to abundance on the farm with a waste-water lagoon system, indicating that this infrastructure may not serve as the sole, or even the primary larval habitat. Adult midges disappeared from both farms from late November until May; however, low numbers of parous female midges were detected in traps set during daylight in the inter-seasonal winter period. This latter finding is especially critical as it provides a potential mechanism for the "overwintering" of BTV in temperate regions such as northern CA. Precise documentation of temporal changes in the annual abundance and

  8. Non-structural protein NS3/NS3a is required for propagation of bluetongue virus in Culicoides sonorensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Bluetongue virus (BTV) causes non-contagious haemorrhagic disease in ruminants and is transmitted by Culicoides spp. biting midges. BTV encodes four non-structural proteins of which NS3/NS3a is functional in virus release. NS3/NS3a is not essential for in vitro virus replication. However...

  9. Comparison of different light sources for trapping Culicoides biting midges, mosquitoes and other dipterans.

    PubMed

    González, Mikel; Alarcón-Elbal, Pedro María; Valle-Mora, Javier; Goldarazena, Arturo

    2016-08-15

    The response of Culicoides biting midges, mosquitoes and other dipterans to different wavelengths was evaluated in a farm meadow in northern Spain. A total of 9449 specimens of 23 species of Culicoides, 5495 other ceratopogonids (non-biting midges), 602 culicids and 12428 other mixed dipterans were captured. Centers for Disease Control and Prevention (CDC) suction light traps fitted with five light emitting diodes (LEDs) (white, green, red, blue, ultraviolet) were run for 15 consecutive nights. Significantly more Culicoides were collected in those traps fitted with green, blue or ultraviolet (UV) lights than in red and white-baited LED traps for the most abundant species captured: C. punctatus (37.5%), C. cataneii (26.5%) and C. obsoletus/C. scoticus (20.4%). Similar results were obtained for non-Culicoides ceratopogonids, mosquitoes and other mixed dipterans. Wavelengths in green (570nm) resulted effective for targeting some Culicoides species, culicids and other midges. In a second trial, the effectiveness of 4-W white and UV tubes was compared to traps fitted with UV LED and a standard incandescent light bulb. More specimens of all taxa were collected with fluorescent black light (UV) traps than with the other light sources, except culicids, which were recovered in high numbers from fluorescent white light traps. PMID:27514882

  10. Management of North American Culicoides biting midges: Current knowledge and research needs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Culicoides biting midges (Diptera: Ceratopogonidae) are biological vectors of two important viruses infecting North American ruminants: bluetongue (BTV) and epizootic hemorrhagic disease (EHDV). While these viruses have been identified for over 60 years, we still lack an adequate understanding of t...

  11. Understanding and exploiting olfaction for the surveillance and control of Culicoides biting midges

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Culicoides midges (Diptera: Ceratopogonidae) are found worldwide with the exception of only a few countries including New Zealand, Patagonia, the Hawaiian Isles and Antarctica. They are a nuisance pest to human beings, but transmit a number of diseases that mainly affect livestock. Like many haema...

  12. Midgut and salivary gland transcriptomes of the arbovirus vector Culicoides sonorensis (Diptera: Ceratopogonidae).

    PubMed

    Campbell, C L; Vandyke, K A; Letchworth, G J; Drolet, B S; Hanekamp, T; Wilson, W C

    2005-04-01

    Numerous Culicoides spp. are important vectors of livestock or human disease pathogens. Transcriptome information from midguts and salivary glands of adult female Culicoides sonorensis provides new insight into vector biology. Of 1719 expressed sequence tags (ESTs) from adult serum-fed female midguts harvested within 5 h of feeding, twenty-eight clusters of serine proteases were derived. Four clusters encode putative iron binding proteins (FER1, FERL, PXDL1, PXDL2), and two clusters encode metalloendopeptidases (MDP6C, MDP6D) that probably function in bloodmeal catabolism. In addition, a diverse variety of housekeeping cDNAs were identified. Selected midgut protease transcripts were analysed by quantitative real-time PCR (q-PCR): TRY1_115 and MDP6C mRNAs were induced in adult female midguts upon feeding, whereas TRY1_156 and CHYM1 were abundant in midguts both before and immediately after feeding. Of 708 salivary gland ESTs analysed, clusters representing two new classes of protein families were identified: a new class of D7 proteins and a new class of Kunitz-type protease inhibitors. Additional cDNAs representing putative immunomodulatory proteins were also identified: 5' nucleotidases, antigen 5-related proteins, a hyaluronidase, a platelet-activating factor acetylhydrolase, mucins and several immune response cDNAs. Analysis by q-PCR showed that all D7 and Kunitz domain transcripts tested were highly enriched in female heads compared with other tissues and were generally absent from males. The mRNAs of two additional protease inhibitors, TFPI1 and TFPI2, were detected in salivary glands of paraffin-embedded females by in situ hybridization. PMID:15796745

  13. INFECTIVITY AND PERSISTENCE OF VESICULAR STOMATITIS VIRUS IN CULICOIDES CELLS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The biting midge, Culicoides sonorensis, was recently shown to be a biologically competent vector for the arbovirus, vesicular stomatitis virus (VSV). While arboviruses can be extremely pathogenic to mammalian cells, they typically do not exert deleterious effects on their insect vectors. Infectio...

  14. "Detection of bluetongue virus in Culicoides cell cultures"

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bluetongue virus (BTV) infects sheep, cattle and other ruminants and is transmitted by Culicoides spp. of biting midges. Cell lines derived from C. sonorensis have been developed at the Arthropod-borne Animal Diseases Research Laboratory. These cell lines have been shown to support BTV replication, ...

  15. Development and evaluation of real-time PCR assays for bloodmeal identification in Culicoides midges.

    PubMed

    VAN DER Saag, M R; Gu, X; Ward, M P; Kirkland, P D

    2016-06-01

    Culicoides (Diptera: Ceratopogonidae) midges are the biological vectors of a number of arboviruses of veterinary importance. However, knowledge relating to the basic biology of some species, including their host-feeding preferences, is limited. Identification of host-feeding preferences in haematophagous insects can help to elucidate the transmission dynamics of the arboviruses they may transmit. In this study, a series of semi-quantitative real-time polymerase chain reaction (qPCR) assays to identify the vertebrate host sources of bloodmeals of Culicoides midges was developed. Two pan-reactive species group and seven species-specific qPCR assays were developed and evaluated. The assays are quick to perform and less expensive than nucleic acid sequencing of bloodmeals. Using these assays, it was possible to rapidly test nearly 700 blood-fed midges of various species from several geographic locations in Australia. PMID:26854008

  16. The effect of salinity on oviposition and egg hatching in Culicoides variipennis sonorensis (Diptera: Ceratopogonidae).

    PubMed

    Linley, J R

    1986-03-01

    The preferences of Culicoides variipennis sonorensis females for oviposition on different salinities were tested in experiments using small wells in a 4 x 4 latin square array. The mean numbers of eggs deposited on wet surfaces on salinites of 0.0, 9.9, 19.0 and 34.0O/OO, were 1212, 659, 287, and 0, respectively. Within a higher range, salinites of 19.0, 23.0, 28.0 and 34.0O/OO yielded mean numbers laid of 110, 3, 6 and 0, respectively. The overall relationship could be reasonably well described by linear regression, implying, under experimental conditions, a decline of 458 eggs laid for every 10O/OO increase in salinity. Eggs laid directly onto salinities up to 19.0O/OO survived and hatched equally well; at 34O/OO, however, no eggs became tanned and none hatched. In contrast, when eggs were laid onto fresh water, then transferred to different salinities 24 hr later, they survived and hatched even at 34O/OO. PMID:3507474

  17. Identification of the Genome Segments of Bluetongue Virus Serotype 26 (Isolate KUW2010/02) that Restrict Replication in a Culicoides sonorensis Cell Line (KC Cells)

    PubMed Central

    Pullinger, Gillian D.; Guimerà Busquets, Marc; Nomikou, Kyriaki; Boyce, Mark; Attoui, Houssam; Mertens, Peter P.

    2016-01-01

    Bluetongue virus (BTV) can infect most ruminant species and is usually transmitted by adult, vector-competent biting midges (Culicoides spp.). Infection with BTV can cause severe clinical signs and can be fatal, particularly in naïve sheep and some deer species. Although 24 distinct BTV serotypes were recognized for several decades, additional ‘types’ have recently been identified, including BTV-25 (from Switzerland), BTV-26 (from Kuwait) and BTV-27 from France (Corsica). Although BTV-25 has failed to grow in either insect or mammalian cell cultures, BTV-26 (isolate KUW2010/02), which can be transmitted horizontally between goats in the absence of vector insects, does not replicate in a Culicoides sonorensis cell line (KC cells) but can be propagated in mammalian cells (BSR cells). The BTV genome consists of ten segments of linear dsRNA. Mono-reassortant viruses were generated by reverse-genetics, each one containing a single BTV-26 genome segment in a BTV-1 genetic-background. However, attempts to recover a mono-reassortant containing genome-segment 2 (Seg-2) of BTV-26 (encoding VP2), were unsuccessful but a triple-reassortant was successfully generated containing Seg-2, Seg-6 and Seg-7 (encoding VP5 and VP7 respectively) of BTV-26. Reassortants were recovered and most replicated well in mammalian cells (BSR cells). However, mono-reassortants containing Seg-1 or Seg-3 of BTV-26 (encoding VP1, or VP3 respectively) and the triple reassortant failed to replicate, while a mono-reassortant containing Seg-7 of BTV-26 only replicated slowly in KC cells. PMID:26890863

  18. CARE, MAINTENANCE, AND EXPERIMENTAL INFECTION OF BITING MIDGES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The laboratory colonization and rearing of Culicoides sonorensis (Diptera: Ceratopogonidae) conducted at the Arthropod-borne Animal Diseases Research Laboratory (ABADRL) have been key to investigations concerning the role of this biting midge as a vector of several viral pathogens of veterinary imp...

  19. Presence in the Balearic Islands (Spain) of the midges Culicoides imicola and Culicoides obsoletus group.

    PubMed

    Miranda, M A; Borràs, D; Rincón, C; Alemany, A

    2003-03-01

    An outbreak of the livestock viral disease bluetongue (BT) was detected during September and October 2000 in the Balearic Islands, Spain. Due to the lack of information about the species of Culicoides (Diptera: Ceratopogonidae) reported in the affected area, six farms in Majorca, four in Minorca and one in Ibiza were selected to carry out surveillance of Culicoides adults using light traps. Here, for the first time, we report the presence in the Balearic Islands of Culicoides imicola Keiffer, the main vector of BT, and the Culicoides obsoletus Meigen group. PMID:12680925

  20. Vector species of Culicoides midges implicated in the 2012‑2014 Bluetongue epidemics in Italy.

    PubMed

    Goffredo, Maria; Catalani, Monica; Federici, Valentina; Portanti, Ottavio; Marini, Valeria; Mancini, Giuseppe; Quaglia, Michela; Santilli, Adriana; Teodori, Liana; Savini, Giovanni

    2015-01-01

    In 2012, serotypes 1 and 4 of bluetongue virus (BTV) entered and co‑circulated in Sardinia. The following year, BTV‑1 spread all over Sardinia and invaded Sicily and the Italian Tyrrenian coast. In 2014, this strain spread extensively in mainland Italy, causing severe outbreaks. In late 2014, BTV‑4 was detected in Southern Italy (Apulia region). This study reports the detection of BTV in species of Culicoides (Diptera: Ceratopogonidae) collected in Italy during the epidemics between 2012 and 2014. A total of 2,925 pools (83,102 midges), sorted from 651 collections made on 339 affected farms of 12 Italian regions, were tested for the presence of BTV by real time polymerase chain reaction (RT‑PCR). The study clearly shows that Culicoides imicola and Obsoletus complex have played a crucial role in the bluetongue (BT) epidemics in Italy in 2012‑2014. Nevertheless, it also shows that other species may have played a role in transmitting BTV during these outbreaks. Culicoides dewulfi and at least 3 species of the Pulicaris complex, namely Culicoides pulicaris, Culicoides newsteadi and Culicoides punctatus, were found positive to BTV. Serotype 1 was detected in all species tested, whereas the BTV‑4 was detected in the Obsoletus complex, C. imicola, and C. newsteadi. PMID:26129664

  1. Influence of carbon dioxide on numbers of Culicoides midges collected with suction light traps in South Africa.

    PubMed

    Venter, G J; Boikanyo, S N B; Majatladi, D M; Morey, L

    2016-03-01

    To implement risk management against diseases transmitted by species of Culicoides Latreille, 1809 (Diptera: Ceratopogonidae), it is essential to identify all potential vectors. Light traps are the most commonly used tool for the collection of Culicoides midges. Given the indiscriminate artificial attraction of light, traps will collect all night-flying insects rather than only livestock-associated Culicoides midges. Factors that may increase the efficacy of traps, especially for livestock-associated Culicoides midges, require investigation. In the present study, results obtained with Centers for Disease Control (CDC) and Onderstepoort light traps baited with carbon dioxide (CO2 ) were compared with those of unbaited controls. Comparisons were made using two replicates of a 4 × 4 randomized Latin square design. With both trap types, the mean numbers of Culicoides midges collected in 16 baited traps were higher than those caught in 16 unbaited traps. Although exceptionally low numbers were collected with the CDC traps, the increases in the numbers and frequency of collection of Culicoides imicola Kieffer, 1913 were more pronounced in the CDC traps compared with the Onderstepoort traps. These results indicate that the addition of CO2 may increase the efficiency of these traps for the collection of C. imicola and other livestock-associated Culicoides species. PMID:26522279

  2. The influence of host number on the attraction of biting midges, Culicoides spp., to light traps.

    PubMed

    Garcia-Saenz, A; McCarter, P; Baylis, M

    2011-03-01

    A preliminary study was undertaken to investigate how the number of sheep below a light-suction trap affects the number of female Culicoides obsoletus Meigen (Diptera: Ceratopogonidae) caught. As the number of sheep increased from zero to three, the number of midges caught increased, but there appeared to be no further increase when six sheep were used. The lack of increase between three and six sheep is attributable to different activity rates on certain nights, perhaps in response to weather, and suggests, therefore, that catches in light traps increase linearly with sheep numbers, at least for small host numbers. PMID:20704653

  3. Morpho-functional identification of abdominal olfactory receptors in the midge Culicoides imicola.

    PubMed

    Sollai, Giorgia; Solari, Paolo; Loy, Francesco; Masala, Carla; Crnjar, Roberto; Liscia, Anna

    2010-11-01

    The aim of the present study was to examine the presence and the possible role of abdominal olfactory sensilla in Culicoides imicola mediating the search for potential hosts and oviposition sites, by means of a morphological, electrophysiological and behavioural approach. The results reported here show that in the midge C. imicola the whole abdomen, comprising the ovipositor, are endowed with three morphotypes of multiporous sensilla that display olfactory sensitivity towards kairomones related to the host-animal skin such as L: -(+)-lactic acid and 1-octen-3-ol, to the host-animal urine such as 3-ethylphenol and 4-propylphenol, and to the potent attractant sesame seed oil. Electrophysiological and behavioural data for the first time suggest in the midge the involvement of abdominal olfactory structures in the choice of the oviposition sites and allow in discussing their possible role in the host-animal localisation. Field experiments showed that light traps baited with the aforementioned compounds elicited a stronger degree of attractiveness on midges with respect to the unbaited traps (control), although to a different extent. Our results, while implying a number of considerations concerning the role of molecules tested as kairomones, also suggest their use in the control of the midge C. imicola population. PMID:20658345

  4. Efficacy of alphacypermethrin-treated high density polyethylene mesh applied to jet stalls housing horses against Culicoides biting midges in South Africa.

    PubMed

    Page, P C; Labuschagne, K; Venter, G J; Schoeman, J P; Guthrie, A J

    2015-05-30

    The efficacy of alphacypermethrin-treated high density polyethylene (HDPE) mesh applied to jet stalls against Culicoides biting midges (Diptera: Ceratopogonidae) was determined by mechanical aspiration of midges from horses and using Onderstepoort 220 V downdraught black light traps in four blocks of a 3 × 2 randomised design under South African field conditions. The alphacypermethrin-treated HDPE mesh applied to the stall significantly (P = 0.008) reduced the number of Culicoides midges, predominantly Culicoides (Avaritia) imicola Kieffer, mechanically aspirated from horses housed in the stall. The mesh reduced the Culicoides midge attack rate in the treated stall compared to the untreated stall and a sentinel horse by 6 times and 14 times, respectively. The number of Culicoides midges and C. imicola collected in light traps from the untreated and alphacypermethrin HDPE mesh-treated stalls did not differ significantly (P = 0.82). Alphacypermethrin-treated HDPE mesh could be used to reduce exposure of horses in jet stalls to Culicoides midges, specifically C. imicola, and the risk of midge-borne Orbivirus transmission. PMID:25794942

  5. An improved, high-throughput method for detection of bluetongue virus RNA in Culicoides midges utilizing infrared-dye-labeled primers for reverse transcriptase PCR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new rapid (less than 6 h from insect-to-results) high-throughput assay is reported that is sensitive and specific for detecting BTV RNA in Culicoides biting midges. Homogenization and extraction of nucleic acids from individual Culicoides specimens were performed in a 96-well plate format using sp...

  6. Mosquitoes and Culicoides biting midges: vector range and the influence of climate change.

    PubMed

    Elbers, A R W; Koenraadt, C J M; Meiswinkel, R

    2015-04-01

    Vector-borne animal diseases pose a continuous and substantial threat to livestock economies around the globe. Increasing international travel, the globalisation of trade, and climate change are likely to play a progressively more important role in the introduction, establishment and spread of arthropod-borne pathogens worldwide. A review of the literature reveals that many climatic variables, functioning singly or in combination, exert varying effects on the distribution and range of Culicoides vector midges and mosquitoes. For example, higher temperatures may be associated with increased insect abundance--thereby amplifying the risk of disease transmission--but there are no indications yet of dramatic shifts occurring in the geographic range of Culicoides midges. However, the same cannot be said for mosquitoes: over the last few decades, multiple Asian species have established themselves in Europe, spread and are unlikely to ever be eradicated. Research on how insects respond to changes in climate is still in its infancy. The authors argue that we need to grasp how other annectant changes, such as extremes in precipitation (drought and flooding), may affect the dispersal capability of mosquitoes. Models are useful for assessing the interplay between mosquito vectors expanding their range and the native flora and fauna; however, ecological studies employing classical mark-release-recapture techniques remain essential for addressing fundamental questions about the survival and dispersal of mosquito species, with the resulting parameters fed directly into new-generation disease transmission models. Studies on the eventual impact of mosquitoes on animal and human health should be tackled through large-scale integrated research programmes. Such an approach calls for more collaborative efforts, along the lines of the One Health Initiative. PMID:26470453

  7. Entomopathogenic Fungus as a Biological Control for an Important Vector of Livestock Disease: The Culicoides Biting Midge

    PubMed Central

    Ansari, Minshad Ali; Pope, Edward C.; Carpenter, Simon; Scholte, Ernst-Jan; Butt, Tariq M.

    2011-01-01

    Background The recent outbreak of bluetongue virus in northern Europe has led to an urgent need to identify control measures for the Culicoides (Diptera: Ceratopogonidae) biting midges that transmit it. Following successful use of the entomopathogenic fungus Metarhizium anisopliae against larval stages of biting midge Culicoides nubeculosus Meigen, we investigated the efficacy of this strain and other fungi (Beauveria bassiana, Isaria fumosorosea and Lecanicillium longisporum) as biocontrol agents against adult C. nubeculosus in laboratory and greenhouse studies. Methodology/Findings Exposure of midges to ‘dry’ conidia of all fungal isolates caused significant reductions in survival compared to untreated controls. Metarhizium anisopliae strain V275 was the most virulent, causing a significantly decrease in midge survival compared to all other fungal strains tested. The LT50 value for strain V275 was 1.42 days compared to 2.21–3.22 days for the other isolates. The virulence of this strain was then further evaluated by exposing C. nubeculosus to varying doses (108–1011 conidia m−2) using different substrates (horse manure, damp peat, leaf litter) as a resting site. All exposed adults were found to be infected with the strain V275 four days after exposure. A further study exposed C. nubeculosus adults to ‘dry’ conidia and ‘wet’ conidia (conidia suspended in 0.03% aq. Tween 80) of strain V275 applied to damp peat and leaf litter in cages within a greenhouse. ‘Dry’ conidia were more effective than ‘wet’ conidia, causing 100% mortality after 5 days. Conclusion/Significance This is the first study to demonstrate that entomopathogenic fungi are potential biocontrol agents against adult Culicoides, through the application of ‘dry’ conidia on surfaces (e.g., manure, leaf litter, livestock) where the midges tend to rest. Subsequent conidial transmission between males and females may cause an increased level of fungi-induced mortality in midges

  8. Biting rates of Culicoides midges (Diptera: Ceratopogonidae) on sheep in northeastern Spain in relation to midge capture using UV light and carbon dioxide-baited traps.

    PubMed

    Gerry, Alec C; Sarto i Monteys, V; Moreno Vidal, J O; Francino, O; Mullens, Bradley A

    2009-05-01

    Biting midges in the genus Culicoides (Diptera: Ceratopogonidae) were collected near sunset by direct aspiration from sheep in northeastern Spain to determine species-specific biting rates and crepuscular activity. Midges were also collected by UV-baited light traps and CO2-baited traps over the same period to compare species diversity and abundance using these common surveillance methods to actual sheep attack rates. Culicoides aspirated from sheep included C. obsoletus, C. parroti, C. scoticus, C. punctatus, and C. imicola. Peak host-seeking activity during the time period examined for the two most commonly collected species (C. obsoletus and C. parroti) occurred just before sunset and activity ceased within 1 h after sunset. Host attack rates near sunset averaged 0.9 midges/min for both species with maximum attack rates of 3/min for C. obsoletus and 4/min for C. parroti. For both species, approximately 35% of midges collected from the sheep were engorged, giving a maximum biting rate of 1.1/min for C. obsoletus and 1.5/min for C. parroti. Traps baited with CO2 collected fewer midges of each species relative to other collection methods. Traps baited with UV light provided a good indication of species richness but significantly underestimated the host attack rate of C. obsoletus and C. parroti while overestimating the host attack rate of C. imicola. Animal-baited collecting is critical to interpret the epidemiological significance of light trap collections used for surveillance of the midge vectors of bluetongue virus and African horse sickness virus. PMID:19496435

  9. Infrared absorption characteristics of Culicoides sonorensis in relation to insect age

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biting midges can transmit diseases that significantly impact livestock in many parts of the world. The age structure of an insect vector population determines its likelihood of transmitting pathogens because the older insects are more likely to be infected than younger ones. Understanding the insec...

  10. Laboratory and field evaluations of chemical and plant-derived potential repellents against Culicoides biting midges in northern Spain.

    PubMed

    González, M; Venter, G J; López, S; Iturrondobeitia, J C; Goldarazena, A

    2014-12-01

    The efficacy of 23 compounds in repelling Culicoides biting midges (Diptera: Ceratopogonidae), particularly Culicoides obsoletus (Meigen) females, was determined by means of a Y-tube olfactometer. The 10 most effective compounds were further evaluated in landing bioassays. The six most promising compounds (including chemical and plant-derived repellents) were evaluated at 10% and 25% concentrations in field assays using Centers for Disease Control (CDC) light traps. At least three compounds showed promising results against Culicoides biting midges with the methodologies used. Whereas olfactometer assays indicated DEET at 1 µg/µL to be the most effective repellent, filter paper landing bioassays showed plant-derived oils to be better. Light traps fitted with polyester mesh impregnated with a mixture of octanoic, decanoic and nonanoic fatty acids at 10% and 25% concentrations collected 2.2 and 3.6 times fewer midges than control traps and were as effective as DEET, which is presently considered the reference standard insect repellent. The best plant-derived product was lemon eucalyptus oil. Although these have been reported as safe potential repellents, the present results indicate DEET and the mixture of organic fatty acids to be superior and longer lasting. PMID:25079042

  11. Foraging range of arthropods with veterinary interest: New insights for Afrotropical Culicoides biting midges (Diptera: Ceratopogonidae) using the ring method.

    PubMed

    Bakhoum, M T; Fall, M; Seck, M T; Gardès, L; Fall, A G; Diop, M; Mall, I; Balenghien, T; Baldet, T; Gimonneau, G; Garros, C; Bouyer, J

    2016-05-01

    The identification of blood meal source of arthropod vector species contributes to the understanding of host-vector-pathogen interactions. The aim of the current work was to identify blood meal source in Culicoides biting midge species, biological vectors of internationally important arboviruses of livestock and equids, using a new ecological approach. We examined the correlation between blood meal source identified in engorged Culicoides females collected in a suction light trap and the available vertebrate hosts along four rings (200, 500, 1000 and 2000 m) centered at the trap site and described the foraging range of the three main vector species of veterinary interest present in the study area, Culicoides imicola, Culicoides kingi and Culicoides oxystoma. The study was performed in four sites localized in the Niayes region of Senegal (West Africa) where recent outbreaks of African horse sickness occurred. Blood meal source identification was carried out by species-specific multiplex PCRs with genomic DNA extracted from the abdomen of engorged females collected during nine night collections for twenty-six collections. The four most abundant hosts present in the studied area (horse, cattle, goat and sheep) were surveyed in each ring zone. The blood meal source varied according to Culicoides species and host availability in each site. C. oxystoma and C. imicola females mainly fed on horses readily available at 200 m maximum from the trap location whereas females of C. kingi fed mainly on cattle, at variable distances from the traps (200 to 2000 m). C. oxystoma may also feed on other vertebrates. We discuss the results in relation with the transmission of Culicoides-borne arboviruses and the species dispersion capacities. PMID:26826391

  12. Quantifying the spatial dependence of Culicoides midge samples collected by Onderstepoort-type blacklight traps: an experimental approach to infer the range of attraction of light traps.

    PubMed

    Rigot, T; Gilbert, M

    2012-06-01

    The emergence of bluetongue disease in Europe has led several countries to rapidly establish large-scale entomological surveys of its vectors, which are midges belonging to the genus Culicoides Latreille, 1809 (Diptera: Ceratopogonidae). These surveys have largely been based on the use of Onderstepoort-type blacklight traps. However, the range of attraction of the traps and the spatial dependence of the samples they provide are unknown, which somewhat complicates subsequent analyses. This paper investigates spatial interaction between Onderstepoort-type blacklight traps based on catches at a central trap placed close to two traps set in consecutive on/off modes. The spatial interaction is inferred from the drop in the number of midges collected in the central trap when nearby traps positioned at 50 m, 100 m or 200 m are turned on. The results showed a significant spatial interaction between traps separated by 50 m for female Culicoides obsoletus/Culicoides scoticus and Culicoides dewulfi. No significant interaction was found for female Culicoides of other species, for male Culicoides, or for traps spaced at ≥100 m. Based on the experimental design geometry and on simple assumptions on the distribution of Culicoides midges in the neighbourhood of the traps, the paper also presents a method to infer the range of attraction of the traps. PMID:22098421

  13. Update on the Culicoides sonorensis transcriptome project: a peek into the molecular biology of the midge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Next Generation Sequencing is transforming the way scientists collect and measure an organism’s genetic background and gene dynamics, while bioinformatics and super-computing are merging to facilitate parallel sample computation and interpretation at unprecedented speeds. Analyzing the complete gene...

  14. The repellent effect of organic fatty acids on Culicoides midges as determined with suction light traps in South Africa.

    PubMed

    Venter, G J; Labuschagne, K; Boikanyo, S N B; Morey, L; Snyman, M G

    2011-09-27

    The efficacy of a 15% (w/w) mixture of octanoic, nonanoic and decanoic acids in light mineral oil to repel Culicoides biting midges (Diptera; Ceratopogonidae) was determined in three replicates of a 4 × 4 Latin square design under South African field conditions. The fatty acids were applied to ± 0.07 m(2) polyester meshes with a mesh size 2-3mm fitted to 220 V 8 W Onderstepoort downdraught light traps. To reduce the relatively strong attraction of the light trap, the black light tubes in the Onderstepoort trap were replaced with 8 W 23 cm white light tubes. The traps were operating overnight next to cattle. Two traps treated with the mixture of fatty acids collected 1.7 times fewer midges than two untreated traps. Although this mixture of fatty acids had shown a repellent effect against a number of blood-feeding insects this is the first indication that it also has a significant repellent effect against Culicoides species and especially Culicoides (Avaritia) imicola Kieffer when applied to polyester mesh. PMID:21592665

  15. Phylogenetic status and matrilineal structure of the biting midge, Culicoides imicola, in Portugal, Rhodes and Israel.

    PubMed

    Dallas, J F; Cruickshank, R H; Linton, Y-M; Nolan, D V; Patakakis, M; Braverman, Y; Capela, R; Capela, M; Pena, I; Meiswinkel, R; Ortega, M D; Baylis, M; Mellor, P S; Mordue Luntz, A J

    2003-12-01

    The biting midge Culicoides imicola Kieffer (Diptera: Ceratopogonidae) is the most important Old World vector of African horse sickness (AHS) and bluetongue (BT). Recent increases of BT incidence in the Mediterranean basin are attributed to its increased abundance and distribution. The phylogenetic status and genetic structure of C. imicola in this region are unknown, despite the importance of these aspects for BT epidemiology in the North American BT vector. In this study, analyses of partial mitochondrial cytochrome oxidase subunit I gene (COI) sequences were used to infer phylogenetic relationships among 50 C. imicola from Portugal, Rhodes, Israel, and South Africa and four other species of the Imicola Complex from southern Africa, and to estimate levels of matrilineal subdivision in C. imicola between Portugal and Israel. Eleven haplotypes were detected in C. imicola, and these formed one well-supported clade in maximum likelihood and Bayesian trees implying that the C. imicola samples comprise one phylogenetic species. Molecular variance was distributed mainly between Portugal and Israel, with no haplotypes shared between these countries, suggesting that female-mediated gene flow at this scale has been either limited or non-existent. Our results provide phylogenetic evidence that C. imicola in the study areas are potentially competent AHS and BT vectors. The geographical structure of the C. imicola COI haplotypes was concordant with that of BT virus serotypes in recent BT outbreaks in the Mediterranean basin, suggesting that population subdivision in its vector can impose spatial constraints on BT virus transmission. PMID:14651651

  16. Comparison of Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry and Molecular Biology Techniques for Identification of Culicoides (Diptera: Ceratopogonidae) Biting Midges in Senegal

    PubMed Central

    Sambou, Masse; Aubadie-Ladrix, Maxence; Fenollar, Florence; Fall, Becaye; Bassene, Hubert; Almeras, Lionel; Sambe-Ba, Bissoume; Perrot, Nadine; Chatellier, Sonia; Faye, Ngor; Parola, Philippe; Wade, Boubacar; Raoult, Didier

    2014-01-01

    Biting midges of the genus Culicoides are implicated as vectors for a wide variety of pathogens. The morphological identification of these arthropods may be difficult because of a lack of detailed investigation of taxonomy for this species in Africa. However, matrix-assisted laser desorption ionization−time of flight mass spectrometry (MALDI-TOF MS) profiling is efficient for arthropod identification at the species level. This study established a spectrum database of Culicoides spp. from Senegal using MALDI-TOF. Identification of Culicoides insects to the species level before mass spectrometry was performed on the basis of morphological characters. MALDI-TOF MS reference spectra were determined for 437 field-caught Culicoides of 10 species. The protein profiles of all tested Culicoides revealed several peaks with mass ranges of 2 to 20 kDa. In a validation study, 72 Culicoides specimens in the target species were correctly identified at the species level with a similarity of 95 to 99.9%. Four Culicoides protein profiles were misidentified. Nevertheless, six SuperSpectra (C. imicola, C. enderleini, C. oxystoma, C. kingi, C. magnus, and C. fulvithorax) were created. Abdomens of midges were used to amplify and sequence a portion of the mitochondrial cytochrome oxidase I gene (COI). The results obtained using the MALDI-TOF MS method were consistent with the morphological identification and similar to the genetic identification. Protein profiling using MALDI-TOF is an efficient approach for the identification of Culicoides spp., and it is economically advantageous for approaches that require detailed and quantitative information of vector species that are collected in field. The database of African Culicoides MS spectra created is the first database in Africa. The COI sequences of five Culicoides species that were previously noncharacterized using molecular methods were deposited in GenBank. PMID:25411169

  17. Colonization of the Mediterranean basin by the vector biting midge species Culicoides imicola: an old story.

    PubMed

    Jacquet, S; Garros, C; Lombaert, E; Walton, C; Restrepo, J; Allene, X; Baldet, T; Cetre-Sossah, C; Chaskopoulou, A; Delecolle, J-C; Desvars, A; Djerbal, M; Fall, M; Gardes, L; de Garine-Wichatitsky, M; Goffredo, M; Gottlieb, Y; Gueye Fall, A; Kasina, M; Labuschagne, K; Lhor, Y; Lucientes, J; Martin, T; Mathieu, B; Miranda, M; Pages, N; Pereira da Fonseca, I; Ramilo, D W; Segard, A; Setier-Rio, M-L; Stachurski, F; Tabbabi, A; Talla Seck, M; Venter, G; Zimba, M; Balenghien, T; Guis, H; Chevillon, C; Bouyer, J; Huber, K

    2015-11-01

    Understanding the demographic history and genetic make-up of colonizing species is critical for inferring population sources and colonization routes. This is of main interest for designing accurate control measures in areas newly colonized by vector species of economically important pathogens. The biting midge Culicoides imicola is a major vector of orbiviruses to livestock. Historically, the distribution of this species was limited to the Afrotropical region. Entomological surveys first revealed the presence of C. imicola in the south of the Mediterranean basin by the 1970s. Following recurrent reports of massive bluetongue outbreaks since the 1990s, the presence of the species was confirmed in northern areas. In this study, we addressed the chronology and processes of C. imicola colonization in the Mediterranean basin. We characterized the genetic structure of its populations across Mediterranean and African regions using both mitochondrial and nuclear markers, and combined phylogeographical analyses with population genetics and approximate Bayesian computation. We found a west/east genetic differentiation between populations, occurring both within Africa and within the Mediterranean basin. We demonstrated that three of these groups had experienced demographic expansions in the Pleistocene, probably because of climate changes during this period. Finally, we showed that C. imicola could have colonized the Mediterranean basin in the Late Pleistocene or Early Holocene through a single event of introduction; however, we cannot exclude the hypothesis involving two routes of colonization. Thus, the recent bluetongue outbreaks are not linked to C. imicola colonization event, but rather to biological changes in the vector or the virus. PMID:26460724

  18. Spatio-temporal occurrence of Culicoides biting midges in the climatic regions of Switzerland, along with large scale species identification by MALDI-TOF mass spectrometry

    PubMed Central

    2012-01-01

    Background Culicoides biting midges are incriminated as biological vectors of a number of viruses, e.g. bluetongue virus. In order to define vector-free periods/areas and to assess the vectorial role of the various Culicoides species, a comprehensive knowledge on their spatio-temporal occurrence is required. Methods Biting midges were monitored on farm sites with livestock in the defined climatic regions, including high altitudes, of Switzerland by overnight trapping at 12 locations once a week over three years using UV-light traps. Based on morphological features, they were separated into three groups (i.e. Obsoletus, Pulicaris, other Culicoides spp.), and identification to the species level was achieved by protein profiling using MALDI-TOF mass spectrometry. Results Around 550,000 biting midges in total were collected, revealing a dominance (82 to 99%) of the Obsoletus group species up to an altitude of 1,200 m and of the Pulicaris group species above 1,500 m (85% at the highest trapping site at 2,130 m). The maximum number of midges collected in a summer night (756 to 19,682) as well as the total number of midges caught over three years (from 6,933 to 149,439) varied highly among the sites, whereas the annual variation in total midge abundance at the locations was statistically insignificant. MALDI-TOF MS of 100 randomly selected individual biting midges per trapping site yielded high quality spectra for 1,187 of the 1,200 (98.9%) specimens of which 1,173 could be assigned to one of the 15 Culicoides species for which biomarker mass sets are available in the reference database. Conclusions There are no biting midge-free zones in all of the agriculturally utilized areas (including alpine summer pastures) of Switzerland. Annual variations of midge numbers at the sampled locations were low, indicating that monitoring of midges should preferably be done by investigating a large number of sites for one season instead of few locations for extended periods of time

  19. The effect of 1-octen-3-ol and 4-methylphenol on Culicoides midge numbers collected with suction light traps in South Africa.

    PubMed

    Venter, G J; Labuschagne, K; Boikanyo, S N B; Majatladi, D M; Morey, L

    2011-01-10

    Despite some shortcomings, suction light traps are the primary monitoring tool for the collection of Culicoides species (Diptera: Ceratopogonidae). Factors that may increase the efficiency of these traps need to be investigated. In the present study the numbers of Culicoides midges collected with two Onderstepoort black light traps baited with a mixture of 1-octen-3-ol and 4-methylphenol, as a potential olfactory cue, were compared to those of two unbaited traps. Comparisons were done in two and three replicates of a 4 × 4 randomized Latin square design in the presence and absence of cattle. The addition of 1-octen-3-ol and 4-methylphenol, released at 9.1 and 15.5mg/h, respectively, did not influence species richness, numbers collected, sex ratios or age-grading results. Comparisons of Culicoides numbers and especially the abundance of Culicoides imicola Kieffer in collections done in the presence and absence of cattle confirm previous findings that show that host animals will be the primary attraction for Culicoides midges and that light traps mostly sample midges already in the near vicinity of the host. PMID:20933332

  20. Farms, pastures and woodlands: the fine-scale distribution of Palearctic Culicoides spp. biting midges along an agro-ecological gradient.

    PubMed

    Rigot, T; Drubbel, M Vercauteren; Delécolle, J-C; Gilbert, M

    2013-03-01

    The spatial epidemiology of Bluetongue virus (BTV) at the landscape level relates to the fine-scale distribution and dispersal capacities of its vectors, midges belonging to the genus Culicoides Latreille (Diptera: Ceratopogonidae). Although many previous researches have carried out Culicoides sampling on farms, little is known of the fine-scale distribution of Culicoides in the landscape immediately surrounding farms. The aim of this study was to gain a better understanding of Culicoides populations at increasing distances from typical dairy farms in north-west Europe, through the use of eight Onderstepoort-type black-light traps positioned along linear transects departing from farms, going through pastures and entering woodlands. A total of 16 902 Culicoides were collected in autumn 2008 and spring 2009. The majority were females, of which more than 97% were recognized as potential vectors. In pastures, we found decreasing numbers of female Culicoides as a function of the distance to the farm. This pattern was modelled by leptokurtic models, with parameters depending on season and species. By contrast, the low number of male Culicoides caught were homogeneously distributed along the transects. When transects entered woodlands, we found a higher abundance of Culicoides than expected considering the distance of the sampling sites to the farm, although this varied according to species. PMID:22897885

  1. Comparison of single- and multi-scale models for the prediction of the Culicoides biting midge distribution in Germany.

    PubMed

    Lühken, Renke; Gethmann, Jörn Martin; Kranz, Petra; Steffenhagen, Pia; Staubach, Christoph; Conraths, Franz J; Kiel, Ellen

    2016-01-01

    This study analysed Culicoides presence-absence data from 46 sampling sites in Germany, where monitoring was carried out from April 2007 until May 2008. Culicoides presence-absence data were analysed in relation to land cover data, in order to study whether the prevalence of biting midges is correlated to land cover data with respect to the trapping sites. We differentiated eight scales, i.e. buffer zones with radii of 0.5, 1, 2, 3, 4, 5, 7.5 and 10 km, around each site, and chose several land cover variables. For each species, we built eight single-scale models (i.e. predictor variables from one of the eight scales for each model) based on averaged, generalised linear models and two multiscale models (i.e. predictor variables from all of the eight scales) based on averaged, generalised linear models and generalised linear models with random forest variable selection. There were no significant differences between performance indicators of models built with land cover data from different buffer zones around the trapping sites. However, the overall performance of multi-scale models was higher than the alternatives. Furthermore, these models mostly achieved the best performance for the different species using the index area under the receiver operating characteristic curve. However, as also presented in this study, the relevance of the different variables could significantly differ between various scales, including the number of species affected and the positive or negative direction. This is an even more severe problem if multi-scale models are concerned, in which one model can have the same variable at different scales but with different directions, i.e. negative and positive direction of the same variable at different scales. However, multi-scale modelling is a promising approach to model the distribution of Culicoides species, accounting much more for the ecology of biting midges, which uses different resources (breeding sites, hosts, etc.) at different scales

  2. Collection and analysis of salivary proteins from the biting midge Culicoides nubeculosus (Diptera: Ceratopogonidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salivary proteins of hematophagous Culicoides spp. are thought to play an important role in pathogen transmission and skin hypersensitivity. Analysis of these proteins, however, has been problematic due to the difficulty in obtaining adequate amounts of secreted Culicoides saliva. In the current stu...

  3. Protection of horses against Culicoides biting midges in different housing systems in Switzerland.

    PubMed

    Lincoln, V J; Page, P C; Kopp, C; Mathis, A; von Niederhäusern, R; Burger, D; Herholz, C

    2015-06-15

    Species belonging to the Culicoides complexes (Diptera, Ceratopogonidae), obsoletus and pulicaris, in Switzerland, are potential vectors of both bluetongue virus (BTV) and African horse sickness virus (AHSV). The epidemic of BTV in 2006 and 2007 in Europe has highlighted the risk of introduction and spread of vector-borne diseases in previously non-endemic areas. As a measure of prevention, as part of an integrated control programme in the event of an outbreak of African horse sickness (AHS), it is of utmost importance to prevent, or substantially reduce, contact between horses and Culicoides. The aim of the present study was to compare the effect of three protection systems, net, fan, repellent, or combinations thereof, with regard to their potential to reduce contact between horses and Culicoides. Three different equine housing systems, including individual boxes (BX), group housing systems (GR), and individual boxes with permanently accessible paddock (BP) were used. The efficacy of the protection systems were evaluated by comparing the total number counts of collected female Culicoides, of non-blood-fed and blood-fed Culicoides, respectively, with UV black light traps. The study was conducted over 3 summer months during 2012 and 2013 each and focused on the efficacy and practicality of the protection systems. The repellent was tested in 2012 only and not further investigated in 2013, as it showed no significant effect in reducing Culicoides collected in the light traps. Net protection system provided the best overall protection for the total number of female Culicoides, non-blood-fed and blood-fed Culicoides in all tested housing systems. The net, with a pore size of 0.1825 mm(2), reduced the total number of Culicoides collected in the housing systems BP, GR and BX by 98%, 85% and 67%, respectively. However, in the GR housing system, no significant difference between the effectiveness of the fan and the net were determined for any of the three Culicoides

  4. PCR identification of culicoid biting midges (Diptera, Ceratopogonidae) of the Obsoletus complex including putative vectors of bluetongue and Schmallenberg viruses

    PubMed Central

    2012-01-01

    Background Biting midges of the Obsoletus species complex of the ceratopogonid genus Culicoides were assumed to be the major vectors of bluetongue virus (BTV) in northern and central Europe during the 2006 outbreak of bluetongue disease (BT). Most recently, field specimens of the same group of species have also been shown to be infected with the newly emerged Schmallenberg virus (SBV) in Europe. A reliable identification of the cryptic species of this group is fundamental for both understanding the epidemiology of the diseases and for targeted vector control. In the absence of classical morphological characters unambiguously identifying the species, DNA sequence-based tests have been established for the distinction of selected species in some parts of Europe. Since specificity and sensitivity of these tests have been shown to be in need of improvement, an alternative PCR assay targeting the mitochondrial cytochrome oxidase subunit I (COI) gene was developed for the identification of the three Obsoletus complex species endemic to Germany (C. obsoletus, C. scoticus, C. chiopterus) plus the isomorphic species C. dewulfi. Methods Biting midges of the genus Culicoides caught by UV light traps all over Germany were morphologically pre-identified to species or complex level. The COI region was amplified from their extracted DNA and sequenced. Final species assignment was done by sequence comparison to GenBank entries and to morphologically identified males. Species-specific consensus sequences were aligned and polymorphisms were utilized to design species-specific primers to PCR-identify specimens when combined with a universal primer. Results The newly developed multiplex PCR assay was successfully tested on genetically defined Obsoletus complex material as well as on morphologically pre-identified field material. The intended major advantage of the assay as compared to other PCR approaches, namely the production of only one single characteristic band for each species

  5. Response of Culicoides sonorensis (Diptera: Ceratopogonidae) to 1-octen-3-ol and three plant-derived repellent formulations in the field.

    PubMed

    Braverman, Y; Wegis, M C; Mullens, B A

    2000-06-01

    The potential attractant 1-octen-3-ol and 3 potential repellents were assayed for activity for Culicoides sonorensis, the primary vector of bluetongue virus in North America. Collections using octenol were low, but numbers in suction traps were greater in the high-octenol treatment (11.5 mg/h) than in the low-octenol treatment (1.2 mg/h) or unbaited control for both sexes. Collections using high octenol, CO2 (approximately 1,000 ml/min), or both showed octenol alone to be significantly less attractive than either of the CO2 treatments and that octenol did not act synergistically with this level of CO2. A plant-derived (Meliaceae) extract with 4.5% of active ingredient (AI) (Ag1000), heptanone solvent, Lice free (2% AI from plant extracts in water), Mosi-guard with 50% Eucalyptus maculata var. citriodora Hook extract, and N,N-diethyl-m-toluamide (deet) were applied to polyester-cotton coarse mesh nets and deployed in conjunction with suction light traps plus CO2. Collections in the trap with deet were 66% lower (P < 0.05) than the heptanone and 56% (P > 0.05) less than the untreated (negative) control. Relative to deet, collections in the traps with the lice repellent, Ag1000, and Mosi-guard were reduced by 15, 34, and 39%, respectively (P > 0.05). The method has promise for field screening of potential repellents before on-animal testing. PMID:10901641

  6. Herpetomonas ztiplika n. sp. (Kinetoplastida: Trypanosomatidae): a parasite of the blood-sucking biting midge Culicoides kibunensis Tokunaga, 1937 (Diptera: Ceratopogonidae).

    PubMed

    Podlipaev, Sergei; Votýpka, Jan; Jirků, Milan; Svobodová, Milena; Lukes, Julius

    2004-04-01

    Herein, we describe the first case of a natural infection of biting midges by a kinetoplastid protozoan. Flagellates from a female Culicoides kibunensis captured in a bird's nest were introduced into culture and characterized by light and electron microscopy. However, because the morphological data were inconclusive, the novel endosymbiont-free trypanosomatid was assigned into Herpetomonas primarily on the basis of the 18S and 5S ribosomal RNA (rRNA) gene sequences. PMID:15165057

  7. Seasonal dynamics of Culicoides (Diptera: Ceratopogonidae) biting midges, potential vectors of African horse sickness and bluetongue viruses in the Niayes area of Senegal

    PubMed Central

    2014-01-01

    Background The African horse sickness epizootic in Senegal in 2007 caused considerable mortality in the equine population and hence major economic losses. The vectors involved in the transmission of this arbovirus have never been studied specifically in Senegal. This first study of the spatial and temporal dynamics of the Culicoides (Diptera: Ceratopogonidae) species, potential vectors of African horse sickness in Senegal, was conducted at five sites (Mbao, Parc Hann, Niague, Pout and Thies) in the Niayes area, which was affected by the outbreak. Methods Two Onderstepoort light traps were used at each site for three nights of consecutive collection per month over one year to measure the apparent abundance of the Culicoides midges. Results In total, 224,665 specimens belonging to at least 24 different species (distributed among 11 groups of species) of the Culicoides genus were captured in 354 individual collections. Culicoides oxystoma, Culicoides kingi, Culicoides imicola, Culicoides enderleini and Culicoides nivosus were the most abundant and most frequent species at the collection sites. Peaks of abundance coincide with the rainy season in September and October. Conclusions In addition to C. imicola, considered a major vector for the African horse sickness virus, C. oxystoma may also be involved in the transmission of this virus in Senegal given its abundance in the vicinity of horses and its suspected competence for other arboviruses including bluetongue virus. This study depicted a site-dependent spatial variability in the dynamics of the populations of the five major species in relation to the eco-climatic conditions at each site. PMID:24690198

  8. Principal climatic and edaphic determinants of Culicoides biting midge abundance during the 2007-2008 bluetongue epidemic in the Netherlands, based on OVI light trap data.

    PubMed

    Scolamacchia, F; VAN DEN Broek, J; Meiswinkel, R; Heesterbeek, J A P; Elbers, A R W

    2014-06-01

    Palaearctic Culicoides midges (Diptera: Ceratopogonidae) represent a vital link in the northward advance of certain arboviral pathogens of livestock such as that caused by bluetongue virus. The effects of relevant ecological factors on weekly Culicoides vector abundances during the bluetongue virus serotype 8 epidemics in the Netherlands in 2007 and 2008 were quantified within a hurdle modelling framework. The relative role of meteorological parameters showed a broadly consistent association across species, with larger catches linked to temperature-related variables and lower wind speed. Moreover, vector abundance was found to be influenced by edaphic factors, likely related to species-specific breeding habitat preferences that differed markedly amongst some species. This is the first study on Culicoides vector species in the Netherlands identified during an entomological surveillance programme, in which an attempt is made to pinpoint the factors that influence midge abundance levels. In addition to providing key inputs into risk-mitigating tools for midge-borne pathogens and disease transmission models, the adoption of methods that explicitly address certain features of abundance datasets (frequent zero-count observations and over-dispersion) helped enhance the robustness of the ecological analysis. PMID:24148154

  9. Effects of Ivermectin on the Susceptibility of Culicoides Sonorensis (Diptera: Ceratopogonidae) to Bluetongue and Epizootic Hemorrhagic Disease Viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ivermectin is one of the most frequently used antiparasitic drugs in the livestock industry. It is toxic to insects, because it can hyperpolarize their nerve and muscle cells and increases cellular membrane permeability to chloride ions, which leads to muscular paralysis. The mortality of Culicoides...

  10. The range of attraction for light traps catching Culicoides biting midges (Diptera: Ceratopogonidae)

    PubMed Central

    2013-01-01

    Background Culicoides are vectors of e.g. bluetongue virus and Schmallenberg virus in northern Europe. Light trapping is an important tool for detecting the presence and quantifying the abundance of vectors in the field. Until now, few studies have investigated the range of attraction of light traps. Methods Here we test a previously described mathematical model (Model I) and two novel models for the attraction of vectors to light traps (Model II and III). In Model I, Culicoides fly to the nearest trap from within a fixed range of attraction. In Model II Culicoides fly towards areas with greater light intensity, and in Model III Culicoides evaluate light sources in the field of view and fly towards the strongest. Model II and III incorporated the directionally dependent light field created around light traps with fluorescent light tubes. All three models were fitted to light trap collections obtained from two novel experimental setups in the field where traps were placed in different configurations. Results Results showed that overlapping ranges of attraction of neighboring traps extended the shared range of attraction. Model I did not fit data from any of the experimental setups. Model II could only fit data from one of the setups, while Model III fitted data from both experimental setups. Conclusions The model with the best fit, Model III, indicates that Culicoides continuously evaluate the light source direction and intensity. The maximum range of attraction of a single 4W CDC light trap was estimated to be approximately 15.25 meters. The attraction towards light traps is different from the attraction to host animals and thus light trap catches may not represent the vector species and numbers attracted to hosts. PMID:23497628

  11. Assessment of population genetic structure in the arbovirus vector midge, Culicoides brevitarsis (Diptera: Ceratopogonidae), using multi-locus DNA microsatellites.

    PubMed

    Onyango, Maria G; Beebe, Nigel W; Gopurenko, David; Bellis, Glenn; Nicholas, Adrian; Ogugo, Moses; Djikeng, Appolinaire; Kemp, Steve; Walker, Peter J; Duchemin, Jean-Bernard

    2015-01-01

    Bluetongue virus (BTV) is a major pathogen of ruminants that is transmitted by biting midges (Culicoides spp.). Australian BTV serotypes have origins in Asia and are distributed across the continent into two distinct episystems, one in the north and another in the east. Culicoides brevitarsis is the major vector of BTV in Australia and is distributed across the entire geographic range of the virus. Here, we describe the isolation and use of DNA microsatellites and gauge their ability to determine population genetic connectivity of C. brevitarsis within Australia and with countries to the north. Eleven DNA microsatellite markers were isolated using a novel genomic enrichment method and identified as useful for genetic analyses of sampled populations in Australia, northern Papua New Guinea (PNG) and Timor-Leste. Significant (P < 0.05) population genetic subdivision was observed between all paired regions, though the highest levels of genetic sub-division involved pair-wise tests with PNG (PNG vs. Australia (FST = 0.120) and PNG vs. Timor-Leste (FST = 0.095)). Analysis of multi-locus allelic distributions using STRUCTURE identified a most probable two-cluster population model, which separated PNG specimens from a cluster containing specimens from Timor-Leste and Australia. The source of incursions of this species in Australia is more likely to be Timor-Leste than PNG. Future incursions of BTV positive C. brevitarsis into Australia may be genetically identified to their source populations using these microsatellite loci. The vector's panmictic genetic structure within Australia cannot explain the differential geographic distribution of BTV serotypes. PMID:26408175

  12. [Efficacy of Flectron-eartags (cypermethrin) for control of midges (Culicoides) as the vectors of bluetongue virus in cattle: field studies and biossays].

    PubMed

    Liebisch, Gabriele; Liebisch, Arndt

    2008-06-01

    When in 2006 infection with bluetongue for the first time occurred in Germany the registered and already against flies and tabanids in cattle proofed Flectron ear tags were used against the blood feeding vector midges (Culicoides) also. However, the efficacy against gnats was not yet proofed. The efficacy of 1 and 2 ear tags (1,067 g cypermethrin per ear tag) per animal was investigated in North Germany with 237 heifers and dairy cows. Midges were caught in suction light traps close to the cattle on pasture or became trapped by mouth operated aspirators directly at the skin of the animal bodies. Within 12,051 specimens of midges 12 species of Culicoides could be identified. On grasslands 3 species, C. obsoletus, C. pulicaris and C. dewulfi were found to be dominant. These 3 species are also known to be vectors of BTV. The toxic efficacy was found for 14 days with 1 ear tag and up to 21 days with 2 ear tags. This duration of efficacy was confirmed in the laboratory with hair clippings from the dorsal line and the ventral abdomen (bioassay). In accordance with workers in the U.S.A. it is concluded that insecticide-impregnated ear tags will reduce the number of biting midges, and by this way the risk of infection with BTV in herds of treated cattle will be reduced as well as in other cattle of a particular region. It is concluded that ear tags are of considerable value as part of an integrated control program for BT, e.g. vaccination. PMID:18605374

  13. Insecticidal sugar baits for adult biting midges.

    PubMed

    Snyder, D; Cernicchiaro, N; Allan, S A; Cohnstaedt, L W

    2016-06-01

    The mixing of an insecticide with sugar solution creates an oral toxin or insecticidal sugar bait (ISB) useful for reducing adult insect populations. The ability of ISBs to kill the biting midge Culicoides sonorensis Wirth and Jones (Diptera: Ceratopogonidae), a vector of bluetongue virus, epizootic hemorrhagic disease and vesicular stomatitis viruses, was tested. The commercial insecticide formulations (percentage active ingredient) tested included bifenthrin, cyfluthrin, deltamethrin, permethrin, dinotefuran, imidacloprid, thiamethoxam and spinosad. Mortality rates were determined for various concentrations of commercial formulations (0.01, 0.05, 0.1, 1, 2 and 3%) and observed at 1, 4, 10 and 24 h post-exposure to the ISB. In the first set of assays, laboratory-reared midges were fed sugar ad libitum and then exposed to insecticide-treated sugar solutions to measure mortality. The second assay assessed competitive feeding: midges were provided with a control sugar solution (10% sucrose) in one vial, and a sugar and insecticide solution in another. Pyrethroid treatments resulted in the greatest mortality in the first hour at the lowest concentrations and spinosad consumption resulted in the least mortality. Biting midges were not deterred from feeding on the 1% ISB solutions despite the presence of an insecticide-free alternative source of sugar. PMID:26789534

  14. Evaluation of matrix-assisted laser desorption/ionization time of flight mass spectrometry for characterization of Culicoides nubeculosus biting midges.

    PubMed

    Kaufmann, C; Ziegler, D; Schaffner, F; Carpenter, S; Pflüger, V; Mathis, A

    2011-03-01

    Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) has shown promise in species identification of insect species. We evaluated its potential to consistently characterize laboratory-reared biting midges of the species Culicoides nubeculosus (Meigen) (Diptera: Ceratopogonidae). Twenty-one reproducible potential biomarker masses for C. nubeculosus were identified under different experimental treatments. These treatments included the homogenization of insects in either water or known concentrations of formic acid. The biomarker masses were present independent of age, gender and different periods of storage of individuals in 70% ethanol (a standard preservation method). It was found that the presence of blood in females reduced the intensity of the MALDI-TOF pattern, necessitating the removal of the abdomen before analysis. The protein profiles of a related non-biting midge, Forcipomyia sp. (Diptera: Ceratopogonidae), and of Aedes japonicus japonicus (Theobald) (Diptera: Culicidae) mosquitoes were also examined and were distinctly different. These findings provide preliminary data to optimize future studies in differentiation of species within the Culicoides genus using MALDI-TOF MS which is a rapid, simple, reliable and cost-effective technique. PMID:21118284

  15. Exploratory trial to determine the efficacy of the PYthon and the PYthon Magnum slow-release insecticide ear tags for the control of midges (Culicoides spp.), attacking sheep and cattle and flies attacking cattle.

    PubMed

    Goosen, H; de Vries, P J T; Fletcher, M G

    2012-08-01

    This study investigated the prophylactic action of the chemical combination zeta-cypermethrin and piperonyl butoxide, administered by means of slow-release insecticide-impregnated ear tags, against biting midges (Culicoides spp) attacking sheep and against midges, horn flies (Haematobia irritant), stable flies (Stomoxys calcitrans), and houseflies (Musca domestica) attacking cattle. Treated sheep and cattle were protected 100 percent against blood-feeding midges for two months and there was a clear reduction in the number of midges collected from treated animals. Three days after the ear tags were attached to cattle, the number of horn flies on the cattle was reduced to practically zero and remained at a low level until the end of the trial (day 85). There was also a strong reduction in the numbers of stable flies and houseflies counted. PMID:22930983

  16. The attraction range of the Onderstepoort 220V light trap for Culicoides biting midges as determined under South African field conditions.

    PubMed

    Venter, G J; Majatladi, D M; Labuschagne, K; Boikanyo, S N B; Morey, L

    2012-11-23

    Despite some limitations suction light traps are the primary tools used for the collection of Culicoides species (Diptera: Ceratopogonidae). The range of attraction of the Onderstepoort light trap is not known but an insight into the range of a trap will determine where the trap must be positioned relative to the hosts present, possible breeding sites and environmental structures in the trapping vicinity. It will therefore contribute to a more meaningful interpretation and comparison of results between trapping events. In the present study the number of Culicoides midges collected in a single trap was compared to those of traps made with an additional trap respectively 1m, 4m and 8.5m away from the first. Treatments between sites were rotated in three replicates of a 4×4 Latin square design. While interactions were found in traps 4m apart no statistically significant interactions were found when they were 8.5m apart. The range of attraction, indicated by the interaction between two traps, will be between 2m and 4m. In interpreting light trap results the limitations of this collection method needs to be taken into consideration. PMID:22704896

  17. Haemoproteus minutus and Haemoproteus belopolskyi (Haemoproteidae): complete sporogony in the biting midge Culicoides impunctatus (Ceratopogonidae), with implications on epidemiology of haemoproteosis.

    PubMed

    Ziegytė, Rita; Palinauskas, Vaidas; Bernotienė, Rasa; Iezhova, Tatjana A; Valkiūnas, Gediminas

    2014-10-01

    Species of Haemoproteus (Haemoproteidae) are cosmopolitan haemosporidian parasites, some of which cause severe diseases in birds. Numerous recent studies address molecular characterization, distribution and genetic diversity of haemoproteids. However, the information about their vectors is scarce. We investigated sporogonic development of two widespread species of Haemoproteus (Haemoproteus minutus and Haemoproteus belopolskyi) in the experimentally infected biting midge Culicoides impunctatus. Wild-caught flies were allowed to take blood meals on naturally infected common blackbirds Turdus merula and icterine warblers Hippolais icterina harboring mature gametocytes of H. minutus (lineage hTURDUS2) and H. belopolskyi (hHIICT1), respectively. The engorged flies were collected, transported to the laboratory, held at 15-18°C, and dissected daily in order to obtain ookinetes, oocysts and sporozoites. Mature ookinetes of H. minutus developed blisteringly rapidly; they were numerous in the midgut content between 1 and 4 h post exposure. Ookinetes of H. belopolskyi developed slower and were reported 1 day post exposure (dpe). Oocysts of both parasites were seen in the midgut wall 3-4 dpe. Sporozoites of H. minutus and H. belopolskyi were first observed in the salivary glands preparations 7 dpe. The percentage of experimentally infected flies with sporozoites of H. minutus was 82.1% and 91.7% with H. belopolskyi. In accordance with microscopy data, polymerase chain reaction amplification and sequencing confirmed presence of the corresponding parasite lineages in experimentally infected biting midges. Sporogonic stages of these parasites were described and illustrated. This study indicates that C. impunctatus is involved in the transmission of deadly H. minutus, which kills captive parrots in Europe. This biting midge is an important vector of avian haemoproteids and worth more attention in epidemiology research of avian haemoproteosis. PMID:25102434

  18. On the study of the transmission networks of blood parasites from SW Spain: diversity of avian haemosporidians in the biting midge Culicoides circumscriptus and wild birds

    PubMed Central

    2013-01-01

    Background Blood-sucking flying insects play a key role in the transmission of pathogens of vector-borne diseases. However, at least for the case of avian malaria parasites, the vast majority of studies focus on the interaction between parasites and vertebrate hosts, but there is a lack of information regarding the interaction between the parasites and the insect vectors. Here, we identified the presence of malaria and malaria-like parasite lineages harbored by the potential vector Culicoides circumscriptus (Kieffer). Also, we identified some nodes of the transmission network connecting parasite lineages, potential insect vectors and avian hosts by comparing Haemoproteus and Plasmodium lineages isolated from insects with those infecting wild birds in this and previous studies. Methods Using a molecular approach, we analysed the presence of blood parasites in a total of 97 biting midges trapped in the Doñana National Park (SW Spain) and surrounding areas. Also, 123 blood samples from 11 bird species were analyzed for the presence of blood parasite infections. Blood parasites Haemoproteus and Plasmodium were identified by amplification of a 478 bp fragment of the mitochondrial cytochrome b gen. Results Thirteen biting midges harboured blood parasites including six Haemoproteus and two Plasmodium lineages, supporting the potential role of these insects on parasite transmission. Moreover, ten (8.1%) birds carried blood parasites. Seven Plasmodium and one Haemoproteus lineages were isolated from birds. Overall, six new Haemoproteus lineages were described in this study. Also, we identified the transmission networks of some blood parasites. Two Haemoproteus lineages, hCIRCUM03 and GAGLA03, were identical to those isolated from Corvus monedula in southern Spain and Garrulus glandarius in Bulgaria, respectively. Furthermore, the new Haemoproteus lineage hCIRCUM05 showed a 99% similarity with a lineage found infecting captive penguins in Japan. Conclusions The comparison

  19. Assessment of vector/host contact: comparison of animal-baited traps and UV-light/suction trap for collecting Culicoides biting midges (Diptera: Ceratopogonidae), vectors of Orbiviruses

    PubMed Central

    2011-01-01

    Background The emergence and massive spread of bluetongue in Western Europe during 2006-2008 had disastrous consequences for sheep and cattle production and confirmed the ability of Palaearctic Culicoides (Diptera: Ceratopogonidae) to transmit the virus. Some aspects of Culicoides ecology, especially host-seeking and feeding behaviors, remain insufficiently described due to the difficulty of collecting them directly on a bait animal, the most reliable method to evaluate biting rates. Our aim was to compare typical animal-baited traps (drop trap and direct aspiration) to both a new sticky cover trap and a UV-light/suction trap (the most commonly used method to collect Culicoides). Methods/results Collections were made from 1.45 hours before sunset to 1.45 hours after sunset in June/July 2009 at an experimental sheep farm (INRA, Nouzilly, Western France), with 3 replicates of a 4 sites × 4 traps randomized Latin square using one sheep per site. Collected Culicoides individuals were sorted morphologically to species, sex and physiological stages for females. Sibling species were identified using a molecular assay. A total of 534 Culicoides belonging to 17 species was collected. Abundance was maximal in the drop trap (232 females and 4 males from 10 species) whereas the diversity was the highest in the UV-light/suction trap (136 females and 5 males from 15 species). Significant between-trap differences abundance and parity rates were observed. Conclusions Only the direct aspiration collected exclusively host-seeking females, despite a concern that human manipulation may influence estimation of the biting rate. The sticky cover trap assessed accurately the biting rate of abundant species even if it might act as an interception trap. The drop trap collected the highest abundance of Culicoides and may have caught individuals not attracted by sheep but by its structure. Finally, abundances obtained using the UV-light/suction trap did not estimate accurately Culicoides

  20. Distribution of Culicoides in Greece.

    PubMed

    Patakakis, Michael J; Papazahariadou, Margarita; Wilson, Anthony; Mellor, Philip S; Frydas, Stavros; Papadopoulos, Orestis

    2009-12-01

    Culicoides biting midges (Diptera: Ceratopogonidae) were trapped between 1999 and 2004 at 122 locations in mainland Greece and on most of the larger Aegean and Ionian islands, using OVI light traps, in order to determine the distribution and seasonal activity of bluetongue virus vectors and other Culicoides species. Thirty-nine Culicoides species were identified, six of which (C. furcillatus, C. impunctatus, C. paolae, C. pictipennis, C. riethi, and C. scoticus) were identified for the first time in Greece. Two of these (C. impunctatus and C. scoticus) may be of veterinary importance due to their role as vectors of bluetongue virus and related orbiviruses. In addition, C. imicola was detected for the first time in mainland Greece. PMID:20836829

  1. Hyaluronidase Activity in Saliva of European Culicoides (Diptera: Ceratopogonidae)

    PubMed Central

    Rádrová, Jana; Vlková, Michaela; Volfová, Věra; Sumová, Petra; Cêtre-Sossah, Catherine; Carpenter, Simon; Darpel, Karin; Rakotoarivony, Ignace; Allène, Xavier; Votýpka, Jan; Volf, Petr

    2016-01-01

    Biting midges of the genus Culicoides transmit pathogens of veterinary importance such as bluetongue virus (Reoviridae: Orbivirus). The saliva of Culicoides is known to contain bioactive molecules including peptides and proteins with vasodilatory and immunomodulative properties. In this study, we detected activity of enzyme hyaluronidase in six Culicoides species that commonly occur in Europe and that are putative vectors of arboviruses. Hyaluronidase was present in all species studied, although its molecular size, sensitivity to SDS, and substrate specificity differed between species. Further studies on the potential effect of hyaluronidase activity on the vector competence of Culicoides species for arboviruses would be beneficial. PMID:26487248

  2. Hyaluronidase Activity in Saliva of European Culicoides (Diptera: Ceratopogonidae).

    PubMed

    Rádrová, Jana; Vlková, Michaela; Volfová, Věra; Sumová, Petra; Cêtre-Sossah, Catherine; Carpenter, Simon; Darpel, Karin; Rakotoarivony, Ignace; Allène, Xavier; Votýpka, Jan; Volf, Petr

    2016-01-01

    Biting midges of the genus Culicoides transmit pathogens of veterinary importance such as bluetongue virus (Reoviridae: Orbivirus). The saliva of Culicoides is known to contain bioactive molecules including peptides and proteins with vasodilatory and immunomodulative properties. In this study, we detected activity of enzyme hyaluronidase in six Culicoides species that commonly occur in Europe and that are putative vectors of arboviruses. Hyaluronidase was present in all species studied, although its molecular size, sensitivity to SDS, and substrate specificity differed between species. Further studies on the potential effect of hyaluronidase activity on the vector competence of Culicoides species for arboviruses would be beneficial. PMID:26487248

  3. Culicoides monitoring in Belgium in 2011: analysis of spatiotemporal abundance, species diversity and Schmallenberg virus detection.

    PubMed

    DE Regge, N; DE Deken, R; Fassotte, C; Losson, B; Deblauwe, I; Madder, M; Vantieghem, P; Tomme, M; Smeets, F; Cay, A B

    2015-09-01

    In 2011, Culicoides (Diptera: Ceratopogonidae) were collected at 16 locations covering four regions of Belgium with Onderstepoort Veterinary Institute (OVI) traps and at two locations with Rothamsted suction traps (RSTs). Quantification of the collections and morphological identification showed important variations in abundance and species diversity between individual collection sites, even for sites located in the same region. However, consistently higher numbers of Culicoides midges were collected at some sites compared with others. When species abundance and diversity were analysed at regional level, between-site variation disappeared. Overall, species belonging to the subgenus Avaritia together with Culicoides pulicaris (subgenus Culicoides) were the most abundant, accounting for 80% and 96% of all midges collected with RSTs and OVI traps, respectively. Culicoides were present during most of the year, with Culicoides obsoletus complex midges found from 9 February until 27 December. Real-time reverse-transcription polymerase chain reaction screening for Schmallenberg virus in the heads of collected midges resulted in the first detection of the virus in August 2011 and identified C. obsoletus complex, Culicoides chiopterus and Culicoides dewulfi midges as putative vector species. At Libramont in the south of Belgium, no positive pools were identified. PMID:25761054

  4. The effect of anthropogenic activity on the occurrence of Culicoides species in the South-Western Khomas Region, Namibia.

    PubMed

    Becker, Elbè; Venter, Gert J; Labuschagne, Karien; Greyling, Telanie; van Hamburg, Huib

    2013-01-01

    Certain species of midges in the genus Culicoides (Diptera: Ceratopogonidae) are vectors of several serious orbiviral (Reoviridae) diseases, one of which, African horse sickness (AHS), was reported in the South-Western area of Khomas Region, Namibia, where it had been believed to be absent. Culicoides imicola, AHS principal vector, was collected in several farms in the area during the winter of 2009. The objective of this study was to determine whether Culicoides midges, especially C. imicola, were favoured at anthropogenic impacted/homestead sites in the arid Khomas Region, where they were not expected to occur under natural, veld conditions. The natural 'background' Culicoides communities where determined from collections made at veld sites, which were then compared to corresponding collections made at homestead sites. Altogether, 10,178 Culicoides midges were collected at homesteads and were then compared to 1,733 individuals collected at veld sites. Culicoides midge numbers were likely boosted in anthropogenic impacted areas/homesteads. This was also the case for the Culicoides species that are vector of AHS. This study indicated the significance of human settlement in the Khomas Region in terms of Culicoides midge abundance and distribution and showed the implications that this may have on the transmission of Culicoides-vectored diseases. PMID:24166479

  5. A New Species of Culicoides (Selfia) (Diptera: Ceratopogonidae) from Southeastern Utah.

    PubMed

    Phillips, Robert A

    2015-09-01

    A new species of biting midge, Culicoides (Selfia) moabensis, is described and illustrated from southeastern Utah. Its relationship to Culicoides (Selfia) multipunctatus Malloch and Culicoides (Selfia) brookmani Wirth is discussed, and modifications to existing keys to adult males and females of C. (Selfia) species are provided. Its abundance, seasonal distribution, and aspects of its reproductive and feeding biology and potential as an arbovirus vector are discussed. PMID:26336237

  6. An Improved, high-throughput method for detection of bluetongue virus RNA in Culicodes midges

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new rapid (less than 6 h from insect-to-results) high-throughput assay is reported that is sensitive and specific for detecting BTV RNA in Culicoides biting midges. Homogenization and extraction of nucleic acids from individual Culicoides specimens were performed in a 96-well plate format using sp...

  7. Feeding behaviour of Culicoides spp. (Diptera: Ceratopogonidae) on cattle and sheep in northeast Germany

    PubMed Central

    2014-01-01

    Background Culicoides spp. play an important role in the transmission of several vector-borne pathogens such as Bluetongue and Schmallenberg virus in Europe. To better understand the biology of local Culicoides species, a study divided into three parts was performed in northeast Germany to elucidate the feeding activity patterns (study A), preferential landing and feeding sites (study B) and host feeding preferences (study C) of Culicoides spp. using cattle and sheep as baits. Methods In study A, the activity of Culicoides spp. was monitored over a 72 h period by collecting insects at regular intervals from the interior of drop traps with cattle or sheep standing inside. In study B, Culicoides spp. were directly aspirated from the coat and fleece of cattle and sheep during the peak activity period of Culicoides. In study C, Culicoides spp. were collected using drop traps with either cattle or sheep standing inside and located 10 m apart. Results In study A, 3,545 Culicoides midges belonging to 13 species were collected, peak activity was observed at sunset. In study B, 2,024 Culicoides midges were collected. A significantly higher number of midges was collected from the belly and flank of cattle in comparison to their head region. In study C, 3,710 Culicoides midges were collected; 3,077 (83%) originated from cattle and 633 (17%) from sheep. Nearly half (46.7%) of the midges collected from cattle were engorged, significantly more than the number of engorged midges collected from sheep (7.5%). Culicoides from the Obsoletus complex (C. obsoletus and C. scoticus) were the most common Culicoides species encountered, followed by C. punctatus. Other species identified were C. dewulfi, C. chiopterus, C. pulicaris, C. lupicaris, C. pallidicornis, C. subfascipennis, C. achrayi, C. stigma, C. griseidorsum and C. subfagineus, the last two species are reported for the first time in Germany. Engorged C. chiopterus were collected in relatively high numbers from sheep

  8. Fungal biological control agents for integrated management of Culicoides spp. (Diptera: Ceratopogonidae) of livestock

    PubMed Central

    Narladkar, B. W.; Shivpuje, P. R.; Harke, P. C.

    2015-01-01

    Aim: Entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana had wide host range against insects and hence these are being exploited as fungal bio-pesticide on a large scale. Both fungi are proved pesticides against many crop pests and farmers are well acquainted with their use on the field. Thus, research was aimed to explore the potency of these fungal spores against larval and adult Culicoides midges, a pest of livestock. Materials and Methods: In-vitro testing of both fungal biological control agents was undertaken in Petri dishes against field collected Culicoides larvae, while in plastic beakers against field collected blood-engorged female Culicoides midges. In-vivo testing was undertaken by spraying requisite concentration of fungal spores on the drainage channel against larvae and resting sites of adult Culicoides midges in the cattle shed. Lethal concentration 50 (LC50) values and regression equations were drawn by following probit analysis using SPSS statistical computerized program. Results: The results of this study revealed LC50 values of 2692 mg and 3837 mg (108 cfu/g) for B. bassiana and M. anisopliae, respectively, against Culicoides spp. larvae. Death of Culicoides larvae due to B. bassiana showed greenish coloration in the middle of the body with head and tail showed intense blackish changes, while infection of M. anisopliae resulted in death of Culicoides larvae with greenish and blackish coloration of body along with total destruction, followed by desquamation of intestinal channel. The death of adult Culicoides midges were caused by both the fungi and after death growth of fungus were very well observed on the dead cadavers proving the efficacy of the fungus. Conclusion: Preliminary trials with both funguses (M. anisopliae, B. bassiana) showed encouraging results against larvae and adults of Culicoides spp. Hence, it was ascertained that, these two fungal molecules can form a part of biological control and alternative to chemical

  9. Ten species of Culicoides Latreille (Diptera: Ceratopogonidae) newly recorded from Thailand.

    PubMed

    Thepparat, Arunrat; Bellis, Glenn; Ketavan, Chitapa; Ruangsittichai, Jiraporn; Sumruayphol, Suchada; Apiwathnasorn, Chamnarn

    2015-01-01

    A survey of biting midges in animal sheds, mangroves and beaches along the Andaman coastal region in southern Thailand between April 2012 and May 2013 collected 10 species of Culicoides which were not previously known from Thailand. These new records are C. arenicola, C. flavipunctatus, C. hui, C. kinari, C. kusaiensis, C. parabubalus, C. quatei, C. spiculae, C. pseudocordiger and C. tamada. An updated checklist of species of Culicoides reported from Thailand is provided. PMID:26624391

  10. Assessment of the repellent effect of citronella and lemon eucalyptus oil against South African Culicoides species.

    PubMed

    Venter, Gert J; Labuschagne, Karien; Boikanyo, Solomon N B; Morey, Liesl

    2014-01-01

    The use of insect repellents to reduce the attack rate of Culicoides species (Diptera:Ceratopogonidae) should form part of an integrated control programme to combat African horse sickness and other diseases transmitted by these blood-feeding midges. In the present study the repellent effects of a commercially available mosquito repellent, a combination of citronella and lemon eucalyptus oils, on Culicoides midges was determined. The number of midges collected with two 220 V Onderstepoort traps fitted with 8 W 23 cm white light tubes and baited with peel-stick patches, each containing 40 mg of active ingredient, was compared with that of two unbaited traps. Two trials were conducted and in each trial the four traps were rotated in two replicates of a 4 x 4 randomised Latin square design. Although more midges were collected in the baited traps, the mean number in the baited and unbaited traps was not significantly different. This mosquito repellent did not influence either the species composition or the physiological groups of Culicoides imicola Kieffer. The higher mean numbers in the baited traps, although not statistically significant, may indicate that this mosquito repellent might even attract Culicoides midges under certain conditions. PMID:25686204

  11. Does covering of farm-associated Culicoides larval habitat reduce adult populations in the United Kingdom?☆

    PubMed Central

    Harrup, L.E.; Gubbins, S.; Barber, J.; Denison, E.; Mellor, P.S.; Purse, B.V.; Carpenter, S.

    2014-01-01

    Culicoides biting midges (Diptera: Ceratopogonidae) are the biological vectors of a range of internationally important arboviruses of livestock, including bluetongue virus (BTV) and the recently emerging Schmallenberg virus (SBV). Culicoides species in the subgenus Avaritia (in the UK: Culicoides obsoletus Meigen, Culicoides scoticus Downes & Kettle, Culicoides dewulfi Goetghebuer and Culicoides chiopterus Meigen) have been implicated in BTV transmission in northern Europe and to a varying degree utilise cattle dung as a larval development substrate. The collection of cattle dung into heaps on farms provides a localised source of Culicoides emergence in close proximity to livestock. This study assesses the impact of covering dung heaps prior to the onset of adult Culicoides activity with the aim of reducing recruitment to the local adult populations at four livestock farms in England. Light suction trap catches of adult Culicoides from these farms were compared with those from four untreated control farms from a wide geographic range across the UK. It was demonstrated that implementing control of emergence from dung heaps did not have a significant impact upon the local adult subgenus Avaritia abundance at the treated farm holdings and that the onset of Culicoides activity was similarly unaffected. Use of this method in isolation is unlikely to have an effect in reducing the risk of BTV and SBV transmission. The implications of these results for control of farm-associated Culicoides in Europe are discussed. PMID:24472769

  12. Evaluation of in vitro methods for assessment of infection of Australian Culicoides spp. with bluetongue viruses.

    PubMed

    Van der Saag, Matthew; Nicholas, Adrian; Ward, Michael; Kirkland, Peter

    2015-01-01

    Biting midges from the genus Culicoides (Diptera: Ceratopogonidae) are the vectors of several globally important arboviruses that affect livestock. These include orbiviruses from the bluetongue virus (BTV) and African horse sickness virus (AHSV) groups and members of the Simbu serogroup of orthobunyaviruses, such as the recently emerged Schmallenberg virus. In this article, the authors evaluate several methods for feeding wild‑caught Australian Culicoides on BTV infected preparations of blood and sucrose. Feeding Culicoides on the membrane of embryonated chicken eggs was identified as the preferred feeding method. Although, cotton wool pads soaked in either virus‑infected blood or virus‑sucrose mixtures were also successful. A non‑destructive nucleic acid extraction technique for the detection of viral RNA in Culicoides was also evaluated as it allows for readily differentiating infected from non‑infected Culicoides. PMID:26741248

  13. Environmental Drivers of Culicoides Phenology: How Important Is Species-Specific Variation When Determining Disease Policy?

    PubMed Central

    Searle, Kate R.; Barber, James; Stubbins, Francesca; Labuschagne, Karien; Carpenter, Simon; Butler, Adam; Denison, Eric; Sanders, Christopher; Mellor, Philip S.; Wilson, Anthony; Nelson, Noel; Gubbins, Simon; Purse, Bethan V.

    2014-01-01

    Since 2006, arboviruses transmitted by Culicoides biting midges (Diptera: Ceratopogonidae) have caused significant disruption to ruminant production in northern Europe. The most serious incursions involved strains of bluetongue virus (BTV), which cause bluetongue (BT) disease. To control spread of BTV, movement of susceptible livestock is restricted with economic and animal welfare impacts. The timing of BTV transmission in temperate regions is partly determined by the seasonal presence of adult Culicoides females. Legislative measures therefore allow for the relaxation of ruminant movement restrictions during winter, when nightly light-suction trap catches of Culicoides fall below a threshold (the ‘seasonally vector free period’: SVFP). We analysed five years of time-series surveillance data from light-suction trapping in the UK to investigate whether significant inter-specific and yearly variation in adult phenology exists, and whether the SVFP is predictable from environmental factors. Because female vector Culicoides are not easily morphologically separated, inter-specific comparisons in phenology were drawn from male populations. We demonstrate significant inter-specific differences in Culicoides adult phenology with the season of Culicoides scoticus approximately eight weeks shorter than Culicoides obsoletus. Species-specific differences in the length of the SVFP were related to host density and local variation in landscape habitat. When the Avaritia Culicoides females were modelled as a group (as utilised in the SFVP), we were unable to detect links between environmental drivers and phenological metrics. We conclude that the current treatment of Avaritia Culicoides as a single group inhibits understanding of environmentally-driven spatial variation in species phenology and hinders the development of models for predicting the SVFP from environmental factors. Culicoides surveillance methods should be adapted to focus on concentrated assessments of species

  14. Environmental drivers of Culicoides phenology: how important is species-specific variation when determining disease policy?

    PubMed

    Searle, Kate R; Barber, James; Stubbins, Francesca; Labuschagne, Karien; Carpenter, Simon; Butler, Adam; Denison, Eric; Sanders, Christopher; Mellor, Philip S; Wilson, Anthony; Nelson, Noel; Gubbins, Simon; Purse, Bethan V

    2014-01-01

    Since 2006, arboviruses transmitted by Culicoides biting midges (Diptera: Ceratopogonidae) have caused significant disruption to ruminant production in northern Europe. The most serious incursions involved strains of bluetongue virus (BTV), which cause bluetongue (BT) disease. To control spread of BTV, movement of susceptible livestock is restricted with economic and animal welfare impacts. The timing of BTV transmission in temperate regions is partly determined by the seasonal presence of adult Culicoides females. Legislative measures therefore allow for the relaxation of ruminant movement restrictions during winter, when nightly light-suction trap catches of Culicoides fall below a threshold (the 'seasonally vector free period': SVFP). We analysed five years of time-series surveillance data from light-suction trapping in the UK to investigate whether significant inter-specific and yearly variation in adult phenology exists, and whether the SVFP is predictable from environmental factors. Because female vector Culicoides are not easily morphologically separated, inter-specific comparisons in phenology were drawn from male populations. We demonstrate significant inter-specific differences in Culicoides adult phenology with the season of Culicoides scoticus approximately eight weeks shorter than Culicoides obsoletus. Species-specific differences in the length of the SVFP were related to host density and local variation in landscape habitat. When the Avaritia Culicoides females were modelled as a group (as utilised in the SFVP), we were unable to detect links between environmental drivers and phenological metrics. We conclude that the current treatment of Avaritia Culicoides as a single group inhibits understanding of environmentally-driven spatial variation in species phenology and hinders the development of models for predicting the SVFP from environmental factors. Culicoides surveillance methods should be adapted to focus on concentrated assessments of species

  15. Culicoides Latreille (Diptera: Ceratopogonidae) taxonomy: Current challenges and future directions

    PubMed Central

    Harrup, L.E.; Bellis, G.A.; Balenghien, T.; Garros, C.

    2015-01-01

    Culicoides Latreille biting midges (Diptera: Ceratopogonidae) cause a significant biting nuisance to humans, livestock and equines, and are the biological vectors of a range of internationally important pathogens of both veterinary and medical importance. Despite their economic significance, the delimitation and identification of species and evolutionary relationships between species within this genus remains at best problematic. To date no phylogenetic study has attempted to validate the subgeneric classification of the genus and the monophyly of many of the subgenera remains doubtful. Many informal species groupings are also known to exist but few are adequately described, further complicating accurate identification. Recent contributions to Culicoides taxonomy at the species level have revealed a high correlation between morphological and molecular analyses although molecular analyses are revealing the existence of cryptic species. This review considers the methods for studying the systematics of Culicoides using both morphological and genetic techniques, with a view to understanding the factors limiting our current understanding of Culicoides biology and hence arbovirus epidemiology. In addition, we examine the global status of Culicoides identification, highlighting areas that are poorly addressed, including the potential implementation of emerging technologies. PMID:25535946

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

    PubMed

    Rádrová, Jana; Mračková, Marie; Galková, Zdenka; Lamka, Jírí; Račka, Karol; Barták, Pavel; Votýpka, Jan

    2016-03-01

    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. PMID:26701798

  17. Culicoides species composition and environmental factors influencing African horse sickness distribution at three sites in Namibia.

    PubMed

    Liebenberg, Danica; Piketh, Stuart; Labuschagne, Karien; Venter, Gert; Greyling, Telane; Mienie, Charlotte; de Waal, Tania; van Hamburg, Huib

    2016-11-01

    African horse sickness (AHS) is one of the most lethal infectious, non-contagious, vector-borne disease of equids. The causative agent, African horse sickness virus (AHSV) is transmitted via Culicoides midges (Diptera: Ceratopogonidae). AHS is endemic to Namibia but detailed studies of Culicoides communities and influencing environmental parameters are limited. This study aims to determine the Culicoides species composition at three different sites and to assess environmental parameters influencing the geographical distribution of AHS in Namibia. Weekly collections of Culicoides were made during the AHS peak season from January to May for 2013 and 2014 using the Onderstepoort 220V UV-light trap. Out of 397 collections made, 124 collections (3287 Culicoides) were analysed for AHSV presence with RT-qPCR. A total of 295 collections were analysed for total Culicoides (all collected Culicoides individuals) and in 75% of these collections the Culicoides were identified to species level. C. imicola was the dominant species with proportional representation of 29.9%. C. subschultzei, C. exspectator and C. ravus each contribute more than 10% to the species composition. The lowest number of Culicoides was collected at Aus 9980, a total of 21819 at Windhoek and the highest number at Okahandja 47343. AHSV was present at all three sites during 2013 but only in Windhoek and Okahandja during 2014. Multivariate analyses of data from the two year survey indicate the environmental parameters in order of importance for the distribution of AHS in Namibia as precipitation>temperature>clay>relative humidity>NDVI. The implication of these findings is that any precipitation event increases Culicoides numbers significantly. Together with these results the high number of species found of which little is known regarding their vector competence, add to the complexity of the distribution of AHS in Namibia. PMID:27491343

  18. Culicoides species abundance and potential over-wintering of African horse sickness virus in the Onderstepoort area, Gauteng, South Africa.

    PubMed

    Venter, Gert J; Labuschagne, Karien; Majatladi, Daphney; Boikanyo, Solomon N B; Lourens, Carina; Ebersohn, Karen; Venter, Estelle H

    2014-01-01

    In South Africa, outbreaks of African horse sickness (AHS) occur in summer; no cases are reported in winter, from July to September. The AHS virus (AHSV) is transmitted almost exclusively by Culicoides midges (Diptera: Ceratopogonidae), of which Culicoides imicola is considered to be the most important vector. The over-wintering mechanism of AHSV is unknown. In this study, more than 500 000 Culicoides midges belonging to at least 26 species were collected in 88 light traps at weekly intervals between July 2010 and September 2011 near horses in the Onderstepoort area of South Africa. The dominant species was C. imicola. Despite relatively low temperatures and frost, at least 17 species, including C. imicola, were collected throughout winter (June-August). Although the mean number of midges per night fell from > 50 000 (March) to < 100 (July and August), no midge-free periods were found. This study, using virus isolation on cell cultures and a reverse transcriptase polymerase chain reaction (RT-PCR) assay, confirmed low infection prevalence in field midges and that the detection of virus correlated to high numbers. Although no virus was detected during this winter period, continuous adult activity indicated that transmission can potentially occur. The absence of AHSV in the midges during winter can be ascribed to the relatively low numbers collected coupled to low infection prevalence, low virus replication rates and low virus titres in the potentially infected midges. Cases of AHS in susceptible animals are likely to start as soon as Culicoides populations reach a critical level. PMID:25686125

  19. Blood Meal Analysis of Culicoides (Diptera: Ceratopogonidae) in Central Tunisia

    PubMed Central

    Slama, Darine; Haouas, Najoua; Mezhoud, Habib; Babba, Hamouda; Chaker, Emna

    2015-01-01

    To evaluate the host preferences of Culicoides species (Diptera: Ceratopogonidae) in Central Tunisia, we identified the source of blood meals of field collected specimens by sequencing of the cytochrome b (cyt b) mitochondrial locus and Prepronociceptine single copy nuclear gene. The study includes the most common and abundant livestock associated species of biting midges in Tunisia: C. imicola, C. jumineri, C. newsteadi, C. paolae, C. cataneii, C. circumscriptus, C. kingi, C. pseudojumineri, C. submaritimus, C. langeroni, C. jumineri var and some unidentified C. species. Analysis of cyt b PCR products from 182 field collected blood-engorged females’ midges revealed that 92% of them fed solely on mammalian species, 1.6% on birds, 2.4% on insects and 0.8% on reptiles. The blast results identified the blood origin of biting midges to the species level with exact or nearly exact matches (≥98%). The results confirm the presence of several Culicoides species, including proven vectors in Central Tunisia. Blood meal analyses show that these species will indeed feed on bigger mammals, thereby highlighting the risk that these viruses will be able to spread in Tunisia. PMID:25793285

  20. Studying Culicoides vectors of BTV in the post-genomic era: resources, bottlenecks to progress and future directions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Culicoides biting midges (Diptera: Ceratopogonidae) are a major vector group responsible for the biological transmission of a wide variety of globally significant arboviruses, including bluetongue virus (BTV). In this review we examine current biological resources for the study of this genus, with a...

  1. Nearly Complete Genome Sequence of Curionopolis Virus, a Culicoides-Related Rhabdovirus Isolated in the Brazilian Amazon Region

    PubMed Central

    Diniz Júnior, José Antonio P.; Cardoso, Jedson F.; Silva, Sandro Patroca; da Silva, Daisy Elaine Andrade; de Oliveira, Layanna F.; é Vasconcelos, Janaina M.; Chiang, Jannifer O.; Dias, Amarilis Aragão; Vianez Júnior, João Lídio da S. G.; Vasconcelos, Pedro F. C.

    2014-01-01

    We report here the first nearly complete genome sequence related to curionopolis virus (CURV), that of strain AR440009, isolated from a pool of Culicoides sp. midges in Serra Norte, Pará State, northern Brazil. All genes showed similarities to those belonging to members of the family Rhabdoviridae. PMID:25395636

  2. A Spatial Simulation Model for the Dispersal of the Bluetongue Vector Culicoides brevitarsis in Australia

    PubMed Central

    Kelso, Joel K.; Milne, George J.

    2014-01-01

    Background The spread of Bluetongue virus (BTV) among ruminants is caused by movement of infected host animals or by movement of infected Culicoides midges, the vector of BTV. Biologically plausible models of Culicoides dispersal are necessary for predicting the spread of BTV and are important for planning control and eradication strategies. Methods A spatially-explicit simulation model which captures the two underlying population mechanisms, population dynamics and movement, was developed using extensive data from a trapping program for C. brevitarsis on the east coast of Australia. A realistic midge flight sub-model was developed and the annual incursion and population establishment of C. brevitarsis was simulated. Data from the literature was used to parameterise the model. Results The model was shown to reproduce the spread of C. brevitarsis southwards along the east Australian coastline in spring, from an endemic population to the north. Such incursions were shown to be reliant on wind-dispersal; Culicoides midge active flight on its own was not capable of achieving known rates of southern spread, nor was re-emergence of southern populations due to overwintering larvae. Data from midge trapping programmes were used to qualitatively validate the resulting simulation model. Conclusions The model described in this paper is intended to form the vector component of an extended model that will also include BTV transmission. A model of midge movement and population dynamics has been developed in sufficient detail such that the extended model may be used to evaluate the timing and extent of BTV outbreaks. This extended model could then be used as a platform for addressing the effectiveness of spatially targeted vaccination strategies or animal movement bans as BTV spread mitigation measures, or the impact of climate change on the risk and extent of outbreaks. These questions involving incursive Culicoides spread cannot be simply addressed with non-spatial models. PMID

  3. Mosquito repellent attracts Culicoides imicola (Diptera: Ceratopogonidae).

    PubMed

    Braverman, Y; Chizov-Ginzburg, A; Mullens, B A

    1999-01-01

    A plant-derived mosquito repellent, based on the oil of Eucalyptus maculata var. citriodora Hook, was evaluated against the biting midge Culicoides imicola Kieffer. Suction black light-traps covered with repellent-impregnated polyester mesh and deployed near horses attracted large numbers of C. imicola, which were seen near the treated net within a few minutes of the start of the experiment. Initial collections in the traps were approximately 3 times as large as those in control traps with untreated mesh. Numbers collected in treated traps were similar to untreated control traps after 4 h. Traps with mesh treated with DEET or another plant-derived (Meliaceae) proprietary product, AG1000, acted as repellents relative to the control. The differential activity of repellents against blood-feeding Diptera is discussed. PMID:10071502

  4. Repellent effect of topical deltamethrin on blood feeding by Culicoides on horses.

    PubMed

    Robin, M; Archer, D; McGowan, C; Garros, C; Gardès, L; Baylis, M

    2015-05-30

    African horse sickness (AHS) is a vectorborne disease spread by Culicoides biting midges. The UK's Department for Environment, Food and Rural Affairs currently suggests using topical deltamethrin for AHS control; however, no data are available regarding its efficacy in the horse. The aims of this study were to investigate the effect of topical deltamethrin on blood feeding by Culicoides on horses and to investigate which Culicoides species blood fed on horses. Three pairs of horses were placed in partially enclosed cages that allowed samples representing the Culicoides interacting with individual horses to be sampled. Four data collection sessions were completed before one horse from each pair was topically treated with 10 ml of 1 per cent deltamethrin solution and another four sessions were then carried out. Collected Culicoides were identified and each biting midge examined to see if it had blood fed. The most abundant species collected were C. chiopterus, C. dewulfi, C. obsoletus and C. scoticus (44.3 per cent) and either C. pulicaris or C. punctatus (34.7 per cent). These species were also more likely to have blood fed than other species, supporting their potential role as AHS vectors if the virus were to reach the UK. There was no significant effect of treatment on blood feeding by Culicoides. The results do not support the use of topical deltamethrin to prevent blood feeding by Culicoides on individual horses; however, the study does not investigate the effect that the widespread use of topical deltamethrin might have on vector numbers or disease transmission from viraemic individuals during an outbreak of AHS. PMID:25948630

  5. Culicoides vector species on three South American camelid farms seropositive for bluetongue virus serotype 8 in Germany 2008/2009.

    PubMed

    Schulz, Claudia; Ziller, Mario; Kampen, Helge; Gauly, Matthias; Beer, Martin; Grevelding, Christoph G; Hoffmann, Bernd; Bauer, Christian; Werner, Doreen

    2015-12-15

    Palearctic species of Culicoides (Diptera, Ceratopogonidae), in particular of the Obsoletus and Pulicaris complexes, were identified as putative vectors of bluetongue virus serotype 8 (BTV-8) on ruminant farms during the epizootic in Germany from 2006 to 2009. BTV may cause severe morbidity and mortality in ruminants and sporadically in South American camelids (SAC). However, the fauna of Culicoides spp. on SAC farms has not been investigated. Therefore, the ceratopogonid fauna was monitored on three farms with BTV-seropositive SAC in Germany. Black-light traps were set up on pastures and in stables from summer 2008 to autumn 2009. Additionally, ceratopogonids were caught in emergence traps mounted on llama dung and dung-free pasture from spring to autumn 2009. After morphological identification, selected Culicoides samples were analysed for BTV-RNA by real-time RT-PCR. The effects of the variables 'location', 'temperature' and 'humidity' on the number of Culicoides caught in black-light traps were modelled using multivariable Poisson regression. In total, 26 species of Culicoides and six other genera of biting midges were identified. The most abundant Culicoides spp. collected both outdoors and indoors with black-light traps belonged to the Obsoletus (77.4%) and Pulicaris (16.0%) complexes. The number of Culicoides peaked in summer, while no biting midges were caught during the winter months. Daily collections of Culicoides were mainly influenced by the location and depended on the interaction of temperature and humidity. In the emergence traps, species of the Obsoletus complex predominated the collections. In summary, the absence of BTV-RNA in any of the analysed Culicoides midges and in the BTV-seropositive SAC on the three farms together with the differences in the pathogenesis of BTV-8 in SAC compared to ruminants suggests a negligible role of SAC in the spread of the virus. Although SAC farms may provide similar suitable habitats for putative Culicoides

  6. Emergence of Culicoides obsoletus group species from farm-associated habitats in Germany.

    PubMed

    Steinke, S; Lühken, R; Balczun, C; Kiel, E

    2016-06-01

    Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) may transmit several arboviruses to ruminant livestock. The species of the Obsoletus group are considered to be among the most important vectors of bluetongue virus (BTV) in northern Europe. As agricultural environments offer suitable habitats for the development of their immature stages, the emergence of adult Culicoides from potential breeding sites was investigated at 20 cattle farms throughout Germany in 2012 and 2013. In analyses of species-specific habitat preferences and relationships between Culicoides abundance in breeding substrates and their physicochemical characteristics, dungheaps emerged as the most important substrate for the development of Culicoides obsoletus sensu stricto (s.s.) (Meigen), whereas Culicoides chiopterus (Meigen) and Culicoides dewulfi Goetghebuer were generally restricted to cowpats. A decreasing pH value was associated with a higher abundance or a higher probability of observing these three species. Furthermore, the abundance of C. obsoletus s.s. was positively related to increasing moisture. Dungheaps were very productive breeding sites for this species and are therefore suggested as a target for potential control measures. PMID:26744290

  7. Impact of biting midges on residential property values in Hervey Bay, Queensland, Australia.

    PubMed

    Ratnayake, Jay; Dale, Pat E; Sipe, Neil G; Daniels, Peter

    2006-03-01

    Biting midges (Culicoides spp.) are an important environmental health issue in Hervey Bay, an area of rapid population growth in Australia. It is also the gateway to a World Heritage area (Great Sandy Strait) and a destination for tourists. The spread of housing developments into suburbs close to midge breeding habitats has led to a problem for the local government responsible for managing biting insects in its area. Suburbs with a severe biting midge problem were found to have significantly lower residential property values than less affected suburbs. The gross reduction in value in due to the midge problem was estimated to range from more than AUS dollar 25 million, based on actual sale price, to more than AUS dollar 55 million, based on the perceptions of the most severely affected residents. PMID:16646336

  8. DEET (N,N-diethyl-meta-toluamide)/PMD (para-menthane-3,8-diol) repellent-treated mesh increases Culicoides catches in light traps.

    PubMed

    Murchie, A K; Clawson, S; Rea, I; Forsythe, I W N; Gordon, A W; Jess, S

    2016-09-01

    Biting midges (Culicoides spp.) are vectors of bluetongue and Schmallenberg viruses. Treatment of mesh barriers is a common method for preventing insect-vectored diseases and has been proposed as a means of limiting Culicoides ingression into buildings or livestock transporters. Assessments using animals are costly, logistically difficult and subject to ethical approval. Therefore, initial screening of test repellents/insecticides was made by applying treatments to mesh (2 mm) cages surrounding Onderstepoort light traps. Five commercial treatments were applied to cages as per manufacturers' application rates: control (water), bendiocarb, DEET/p-menthane-3,8-diol (PMD) repellent, Flygo (a terpenoid based repellent) and lambda-cyhalothrin. The experimental design was a 5 × 5 Latin square, replicated in time and repeated twice. Incongruously, the traps surrounded by DEET/PMD repellent-treated mesh caught three to four times more Obsoletus group Culicoides (the commonest midge group) than the other treatments. A proposed hypothesis is that Obsoletus group Culicoides are showing a dose response to DEET/PMD, being attracted at low concentrations and repelled at higher concentrations but that the strong light attraction from the Onderstepoort trap was sufficient to overcome close-range repellence. This study does not imply that DEET/PMD is an ineffective repellent for Culicoides midges in the presence of an animal but rather that caution should be applied to the interpretation of light trap bioassays. PMID:27179956

  9. Potential for bluetongue virus persistence in insect cells.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A potential persistent bluetongue virus (BTV) infection of an insect cell line is under investigation. Culicoides sonorensis, a biting midge, is the primary vector in the U.S. for BTV, which infects sheep, cattle, and wild ruminants. A Culicoides cell line (KC cell line) developed at the ABADRL has...

  10. Assessment of Survival and Body Size Variation of Culicoides imicola (Diptera: Ceratopogonidae) as Functions of “Candidatus Cardinium” (Bacteroidetes) Infection Status

    PubMed Central

    Morag, N.; Mullens, B. A.

    2013-01-01

    “Candidatus Cardinium hertigii” (Bacteroidetes) is a maternally inherited endosymbiont known from several arthropods. Its mechanisms for persistence in host populations are mostly reproductive manipulation, though it has been occasionally reported to improve fitness parameters in several hosts. In Culicoides (Diptera: Ceratopogonidae) biting midges, the prevalence of “Candidatus Cardinium” infection was documented as moderate, with no detectable sex bias. We therefore investigated whether “Candidatus Cardinium” affects important fitness parameters, such as survival and body size, in Culicoides imicola, a dominant vector species. Field-collected midges were trapped and analyzed for survival under different environmental conditions and antibiotic treatment, taking into account “Candidatus Cardinium” infection status and parity status (i.e., parous or nulliparous). Additionally, wing lengths were measured as a proxy parameter for body size and analyzed together with “Candidatus Cardinium” infection data. The findings revealed no difference in survival of Culicoides infected with “Candidatus Cardinium” and that of uninfected midges in both parity states and under all tested conditions: optimal, starvation, heat, and antibiotic treatment. Beyond survival, no wing length difference was found for “Candidatus Cardinium”-infected versus uninfected midges. In aggregate, these findings support our conclusion that “Candidatus Cardinium” does not have an overt effect on the survival and size of adult C. imicola midges. “Candidatus Cardinium” may affect immature stages or may alter adult reproductive performance. PMID:23913434

  11. Host preferences and circadian rhythm of Culicoides (Diptera: Ceratopogonidae), vectors of African horse sickness and bluetongue viruses in Senegal.

    PubMed

    Fall, Moussa; Fall, Assane G; Seck, Momar T; Bouyer, Jérémy; Diarra, Maryam; Lancelot, Renaud; Gimonneau, Geoffrey; Garros, Claire; Bakhoum, Mame T; Faye, Ousmane; Baldet, Thierry; Balenghien, Thomas

    2015-09-01

    African horse sickness- and bluetongue virus are orbiviruses transmitted by Culicoides biting midges (Diptera: Ceratopogonidae) to horses and to ruminants, respectively. Since the last epizootic outbreak of African horse sickness in 2007 in Senegal, extensive investigations have been undertaken to improve our knowledge on Culicoides species involved locally in the transmission of the virus. The purpose of this study was to compare and quantify the host preferences of potential vectors of these orbiviruses on horse and sheep and to study their circadian rhythm. We found that Culicoides oxystoma and species of the sub-genus Avaritia (Culicoides imicola, Culicoides bolitinos and Culicoides pseudopallidipennis) had a preference for horse when compared to sheep (the predicted ratio between horse and sheep was 80 for C. oxystoma and 26 for C. imicola), and were mostly crepuscular: C. oxystoma had continuous activity throughout the diel with peaks in numbers collected after sunrise and sunset, while C. imicola was mostly nocturnal with peak after sunset. Unexpectedly, species of the subgenus Lasiohelea was also collected during this study. This diurnal biting species was a nuisance pest for both animal species used as bait. PMID:26099680

  12. Culicoides hildebrandoi, a new species of the reticulatus species group from the Brazilian Amazon Region (Diptera, Ceratopogonidae)

    PubMed Central

    Farias, Emanuelle de Sousa; Pereira Júnior, Antonio Marques; Felippe-Bauer, Maria Luiza; Pessoa, Felipe Arley Costa; Medeiros, Jansen Fernandes; Santarém, Maria Clara Alves

    2016-01-01

    Abstract A new species of biting midge (Diptera: Ceratopogonidae), Culicoides hildebrandoi sp. n., is described and illustrated based on female and male specimens from the states of Amazonas and Rondônia, Brazil. This new species belongs to the reticulatus species group and differs from the 24 other species of this group by the elongate slightly swollen 3rd palpal segment with scattered capitate sensilla but lacking a sensory pit. PMID:27110160

  13. Species Diversity and Seasonal Distribution of Culicoides spp. (Diptera: Ceratopogonidae) in Jeju-do, Republic of Korea

    PubMed Central

    Kim, Heung Chul; Bellis, Glenn A.; Kim, Myung-Soon; Klein, Terry A.; Gopurenko, David; Cai, Du-Cheng; Seo, Hyun-Ji; Cho, In-Soo; Park, Jee-Yong

    2015-01-01

    Biting midges belonging to the genus Culicoides (Diptera: Ceratopogonidae) were collected by Mosquito Magnet® and black light traps at 5 sites on Jeju-do, Republic of Korea (Korea), from May-November 2013 to determine species diversity and seasonal distribution. A total of 4,267 specimens were collected, of which 99.9% were female. The most common species was Culicoides tainanus (91.8%), followed by C. lungchiensis (7.2%) and C. punctatus (0.6%), while the remaining 4 species accounted for <0.5% of all Culicoides spp. that were collected. High numbers of C. tainanus were collected in May, followed by decreasing numbers through August, and then increasing numbers through November when surveillance was terminated. Peak numbers of C. lungchiensis were collected during September, with low numbers collected from May-August and October-November. The presence of C. lungchiensis in Korea was confirmed by morphological and molecular analyses. PMID:26323852

  14. Species Diversity and Seasonal Distribution of Culicoides spp. (Diptera: Ceratopogonidae) in Jeju-do, Republic of Korea.

    PubMed

    Kim, Heung Chul; Bellis, Glenn A; Kim, Myung-Soon; Klein, Terry A; Gopurenko, David; Cai, Du-Cheng; Seo, Hyun-Ji; Cho, In-Soo; Park, Jee-Yong

    2015-08-01

    Biting midges belonging to the genus Culicoides (Diptera: Ceratopogonidae) were collected by Mosquito Magnet(®) and black light traps at 5 sites on Jeju-do, Republic of Korea (Korea), from May-November 2013 to determine species diversity and seasonal distribution. A total of 4,267 specimens were collected, of which 99.9% were female. The most common species was Culicoides tainanus (91.8%), followed by C. lungchiensis (7.2%) and C. punctatus (0.6%), while the remaining 4 species accounted for <0.5% of all Culicoides spp. that were collected. High numbers of C. tainanus were collected in May, followed by decreasing numbers through August, and then increasing numbers through November when surveillance was terminated. Peak numbers of C. lungchiensis were collected during September, with low numbers collected from May-August and October-November. The presence of C. lungchiensis in Korea was confirmed by morphological and molecular analyses. PMID:26323852

  15. Development and validation of IIKC: an interactive identification key for Culicoides (Diptera: Ceratopogonidae) females from the Western Palaearctic region

    PubMed Central

    2012-01-01

    Background and methods The appearance of bluetongue virus (BTV) in 2006 within northern Europe exposed a lack of expertise and resources available across this region to enable the accurate morphological identification of species of Culicoides Latreille biting midges, some of which are the major vectors of this pathogen. This work aims to organise extant Culicoides taxonomic knowledge into a database and to produce an interactive identification key for females of Culicoides in the Western Palaearctic (IIKC: Interactive identification key for Culicoides). We then validated IIKC using a trial carried out by six entomologists based in this region with variable degrees of experience in identifying Culicoides. Results The current version of the key includes 98 Culicoides species with 10 morphological variants, 61 descriptors and 837 pictures and schemes. Validation was carried out by six entomologists as a blind trial with two users allocated to three classes of expertise (beginner, intermediate and advanced). Slides were identified using a median of seven steps and seven minutes and user confidence in the identification varied from 60% for failed identifications to a maximum of 80% for successful ones. By user class, the beginner group successfully identified 44.6% of slides, the intermediate 56.8% and the advanced 74.3%. Conclusions Structured as a multi-entry key, IIKC is a powerful database for the morphological identification of female Culicoides from the Western Palaearctic region. First developed for use as an interactive identification key, it was revealed to be a powerful back-up tool for training new taxonomists and to maintain expertise level. The development of tools for arthropod involvement in pathogen transmission will allow clearer insights into the ecology and dynamics of Culicoides and in turn assist in understanding arbovirus epidemiology. PMID:22776566

  16. Multiple vectors and their differing ecologies: observations on two bluetongue and African horse sickness vector Culicoides species in South Africa.

    PubMed

    Meiswinkel, R; Labuschagne, K; Baylis, M; Mellor, P S

    2004-01-01

    Blacklight traps were used to collect Culicoides biting midges weekly between September 1996 and August 1998 at 40 sites distributed equidistantly across South Africa. The seasonal and geographic prevalences of 86 species of Culicoides were elucidated simultaneously, and included C. imicola Kieffer and C. bolitinos Meiswinkel the principal vectors of bluetongue (BT) and African horse sickness (AHS) in the region. These two species were amongst the most prevalent Culicoides to be found and, together, comprised >50% of the more than three million biting midges captured. The data are presented as coloured matrices, and are transformed also into inverse distance weighting (IDW) interpolative maps. The data reveal that the prevalence of each vector is somewhat fractured and it is posited that this is (in part) due to significant differences in their respective breeding habitats. The results illustrate also that the presence of multiple vectors (in any region of the world) will complicate both the epidemiology of the orbiviral diseases they transmit and the formulation of rational livestock movement and disease control strategies. This is especially true for southern Europe where the recent devastating cycle of BT has been shown to involve at least three vectors. Finally, the influence that man has on the development of large foci of vector Culicoides around livestock may be less important than previously suggested but must be investigated further. PMID:20419682

  17. Haemoproteus tartakovskyi (Haemoproteidae): Complete sporogony in Culicoides nubeculosus (Ceratopogonidae), with implications for avian haemoproteid experimental research.

    PubMed

    Žiegytė, Rita; Bernotienė, Rasa; Palinauskas, Vaidas; Valkiūnas, Gediminas

    2016-01-01

    Numerous recent studies have addressed the molecular characterization, distribution and genetic diversity of Haemoproteus spp. (Haemoproteidae). Some species of these blood parasites cause severe disease in birds, and heavy infections are often lethal in biting midges (Ceratopogonidae) and other blood-sucking insects. However, information about the vectors of haemoproteids is scarce. This presents an obstacle for better understanding the mechanisms of host-parasite interactions and the epidemiology of haemoproteosis. Here we investigated the sporogonic development of Haemoproteus tartakovskyi, a widespread bird parasite, in experimentally infected biting midges, Culicoides nubeculosus. These biting midges are widespread in the Europe. The insects were cultivated under laboratory conditions. Unfed females were allowed to take blood meals on wild caught siskins Carduelis spinus naturally infected with H. tartakovskyi (lineage hSISKIN1). Engorged females were maintained at 22-23 °C, dissected at intervals, and examined for sporogonic stages. Mature ookinetes of H. tartakovskyi were seen in the midgut content between 6 and 48 h post infection, oocysts were observed in the midgut wall 3-4 days post infection (dpi). Sporozoites were first reported in the salivary gland preparations 7 dpi. In accordance with microscopy data, polymerase chain reaction amplification and sequencing confirmed presence of the corresponding parasite lineage in experimentally infected biting midges. This study indicates that C. nubeculosus willingly takes blood meals on birds and is a vector of H. tartakovskyi. These biting midges are readily amenable to cultivation under laboratory conditions. Culicoides nubeculosus transmits Haemoproteus parasites infecting parrots, owls and siskins, birds belonging to different families and orders. Thus, this vector provides a convenient model for experimental research with avian haemoproteids. PMID:26616347

  18. Detection of African horse sickness virus in Culicoides imicola pools using RT-qPCR.

    PubMed

    de Waal, Tania; Liebenberg, Danica; Venter, Gert J; Mienie, Charlotte Ms; van Hamburg, Huib

    2016-06-01

    African horse sickness (AHS) is an infectious, non-contagious arthropod-borne disease of equids, caused by the African horse sickness virus (AHSV), an orbivirus of the Reoviridae family. It is endemic in sub-Saharan Africa and thought to be the most lethal viral disease of horses. This study focused on detection of AHSV in Culicoides imicola (Diptera: Ceratopogonidae) pools by the application of a RT-qPCR. Midges were fed on AHSV-infected blood. A single blood-engorged female was allocated to pools of unfed nulliparous female midges. Pool sizes varied from 1 to 200. RNA was extracted and prepared for RT-qPCR. The virus was successfully detected and the optimal pool size for the limit of detection of the virus was determined at a range between 1 to 25. Results from this investigation highlight the need for a standardized protocol for AHSV investigation in Culicoides midges especially for comparison among different studies and for the determination of infection rate. PMID:27232141

  19. Characterization of Viral Communities of Biting Midges and Identification of Novel Thogotovirus Species and Rhabdovirus Genus.

    PubMed

    Temmam, Sarah; Monteil-Bouchard, Sonia; Robert, Catherine; Baudoin, Jean-Pierre; Sambou, Masse; Aubadie-Ladrix, Maxence; Labas, Noémie; Raoult, Didier; Mediannikov, Oleg; Desnues, Christelle

    2016-01-01

    More than two thirds of emerging viruses are of zoonotic origin, and among them RNA viruses represent the majority. Ceratopogonidae (genus Culicoides) are well-known vectors of several viruses responsible for epizooties (bluetongue, epizootic haemorrhagic disease, etc.). They are also vectors of the only known virus infecting humans: the Oropouche virus. Female midges usually feed on a variety of hosts, leading to possible transmission of emerging viruses from animals to humans. In this context, we report here the analysis of RNA viral communities of Senegalese biting midges using next-generation sequencing techniques as a preliminary step toward the identification of potential viral biohazards. Sequencing of the RNA virome of three pools of Culicoides revealed the presence of a significant diversity of viruses infecting plants, insects and mammals. Several novel viruses were detected, including a novel Thogotovirus species, related but genetically distant from previously described tick-borne thogotoviruses. Novel rhabdoviruses were also detected, possibly constituting a novel Rhabdoviridae genus, and putatively restricted to insects. Sequences related to the major viruses transmitted by Culicoides, i.e., African horse sickness, bluetongue and epizootic haemorrhagic disease viruses were also detected. This study highlights the interest in monitoring the emergence and circulation of zoonoses and epizooties using their arthropod vectors. PMID:26978389

  20. Characterization of Viral Communities of Biting Midges and Identification of Novel Thogotovirus Species and Rhabdovirus Genus

    PubMed Central

    Temmam, Sarah; Monteil-Bouchard, Sonia; Robert, Catherine; Baudoin, Jean-Pierre; Sambou, Masse; Aubadie-Ladrix, Maxence; Labas, Noémie; Raoult, Didier; Mediannikov, Oleg; Desnues, Christelle

    2016-01-01

    More than two thirds of emerging viruses are of zoonotic origin, and among them RNA viruses represent the majority. Ceratopogonidae (genus Culicoides) are well-known vectors of several viruses responsible for epizooties (bluetongue, epizootic haemorrhagic disease, etc.). They are also vectors of the only known virus infecting humans: the Oropouche virus. Female midges usually feed on a variety of hosts, leading to possible transmission of emerging viruses from animals to humans. In this context, we report here the analysis of RNA viral communities of Senegalese biting midges using next-generation sequencing techniques as a preliminary step toward the identification of potential viral biohazards. Sequencing of the RNA virome of three pools of Culicoides revealed the presence of a significant diversity of viruses infecting plants, insects and mammals. Several novel viruses were detected, including a novel Thogotovirus species, related but genetically distant from previously described tick-borne thogotoviruses. Novel rhabdoviruses were also detected, possibly constituting a novel Rhabdoviridae genus, and putatively restricted to insects. Sequences related to the major viruses transmitted by Culicoides, i.e., African horse sickness, bluetongue and epizootic haemorrhagic disease viruses were also detected. This study highlights the interest in monitoring the emergence and circulation of zoonoses and epizooties using their arthropod vectors. PMID:26978389

  1. Bluetongue, Schmallenberg - what is next? Culicoides-borne viral diseases in the 21st Century

    PubMed Central

    2014-01-01

    In the past decade, two pathogens transmitted by Culicoides biting midges (Diptera: Ceratopogonidae), bluetongue virus and Schmallenberg virus, have caused serious economic losses to the European livestock industry, most notably affecting sheep and cattle. These outbreaks of arboviral disease have highlighted large knowledge gaps on the biology and ecology of indigenous Culicoides species. With these research gaps in mind, and as a means of assessing what potential disease outbreaks to expect in the future, an international workshop was held in May 2013 at Wageningen University, The Netherlands. It brought together research groups from Belgium, France, Germany, Spain, Switzerland, United Kingdom and The Netherlands, with diverse backgrounds in vector ecology, epidemiology, entomology, virology, animal health, modelling, and genetics. Here, we report on the key findings of this workshop. PMID:24685104

  2. Evaluation of naled applied as a thermal fog against Culicoides furens (Diptera: Ceratopogonidae).

    PubMed

    Linley, J R; Parsons, R E; Winner, R A

    1987-09-01

    Naled/diesel oil (1:99), applied as a thermal fog, was tested against the biting midge Culicoides furens. The insects were confined in small cages suspended at 4 heights on poles at progressively greater distances from the fog release point. In terms of population survival 24 hr after treatment, a parabolic equation accurately described the regression of percent survival on distance from the release point. If 10% survival is considered as the maximum acceptable, then the equation predicts adequate control up to 19.6 m (64.3 ft) from the fog release point. PMID:3504923

  3. Genetic characterization and molecular identification of the bloodmeal sources of the potential bluetongue vector Culicoides obsoletus in the Canary Islands, Spain

    PubMed Central

    2012-01-01

    Background Culicoides (Diptera: Ceratopogonidae) biting midges are vectors for a diversity of pathogens including bluetongue virus (BTV) that generate important economic losses. BTV has expanded its range in recent decades, probably due to the expansion of its main vector and the presence of other autochthonous competent vectors. Although the Canary Islands are still free of bluetongue disease (BTD), Spain and Europe have had to face up to a spread of bluetongue with disastrous consequences. Therefore, it is essential to identify the distribution of biting midges and understand their feeding patterns in areas susceptible to BTD. To that end, we captured biting midges on two farms in the Canary Islands (i) to identify the midge species in question and characterize their COI barcoding region and (ii) to ascertain the source of their bloodmeals using molecular tools. Methods Biting midges were captured using CDC traps baited with a 4-W blacklight (UV) bulb on Gran Canaria and on Tenerife. Biting midges were quantified and identified according to their wing patterns. A 688 bp segment of the mitochondrial COI gene of 20 biting midges (11 from Gran Canaria and 9 from Tenerife) were PCR amplified using the primers LCO1490 and HCO2198. Moreover, after selected all available females showing any rest of blood in their abdomen, a nested-PCR approach was used to amplify a fragment of the COI gene from vertebrate DNA contained in bloodmeals. The origin of bloodmeals was identified by comparison with the nucleotide-nucleotide basic alignment search tool (BLAST). Results The morphological identification of 491 female biting midges revealed the presence of a single morphospecies belonging to the Obsoletus group. When sequencing the barcoding region of the 20 females used to check genetic variability, we identified two haplotypes differing in a single base. Comparison analysis using the nucleotide-nucleotide basic alignment search tool (BLAST) showed that both haplotypes belong to

  4. Quorum Quenching Bacillus sonorensis Isolated from Soya Sauce Fermentation Brine

    PubMed Central

    Yin, Wai-Fong; Tung, Hun-Jiat; Sam, Choon-Kook; Koh, Chong-Lek; Chan, Kok-Gan

    2012-01-01

    An N-acylhomoserine lactone (AHL)-degrading bacterial strain, L62, was isolated from a sample of fermentation brine of Chinese soya sauce by using rich medium agar supplemented with soya sauce (10% v/v). L62, a rod-shaped Gram positive bacterium with amylolytic activity, was phylogentically related to Bacillus sonorensis by 16S ribosomal DNA and rpoB sequence analyses. B. sonorensis L62 efficiently degraded N-3-oxohexanoyl homoserine lactone and N-octanoylhomoserine lactone. However, the aiiA homologue, encoding an autoinducer inactivation enzyme catalyzing the degradation of AHLs, was not detected in L62, suggesting the presence of a different AHL-degrading gene in L62. To the best of our knowledge, this is the first report of AHL-degrading B. sonorensis from soya sauce liquid state fermentation. PMID:22666018

  5. Characterizing the species composition of European Culicoides vectors by means of the Köppen-Geiger climate classification

    PubMed Central

    2013-01-01

    Background Biting midges of the genus Culicoides spp. (Diptera: Ceratopogonidae) are vectors for the Bluetongue virus, the African horse sickness virus and the recently emerged Schmallenberg virus. Here, species of the C. obsoletus complex, the C. pulicaris complex and C. imicola were considered. The objective was to compile a map of these Culicoides species and their relation to the popular climate classification defined by Wladimir Köppen and Rudolf Geiger to provide a quick view on the species composition in Europe. Findings Major parts of Central and Northern Europe are covered by a warm temperate fully humid climate, characterized by warm summers. For this so-called Cfb climate fractions of 89% C. obsoletus complex and 11% C. pulicaris complex were estimated. Further investigations comprise the continental climate Dfb (76% C. obsoletus, 24% C. pulicaris), the warm temperate climate with hot summers Cfa (35% C. obsoletus, 65% C. pulicaris), the warm temperate dry climate, characterized by warm summers Csb (38% C. obsoletus, 51% C. pulicaris, 11% C. imicola) and the warm temperate dry climate with hot summers Csa of the Mediterranean area (11% C. obsoletus, 12% C. pulicaris, 77% C. imicola). Conclusions A highly significant association coefficient of RV = 0.64 (Cramer’s V) confirms the correlation between Culicoides spp. and climate zones. Moreover, climate projections for the end of the century give an impression on expected changes in the European Culicoides spp. composition. PMID:24267276

  6. A survey of Culicoides developmental sites on a farm in northern Spain, with a brief review of immature habitats of European species.

    PubMed

    González, Mikel; López, Sergio; Mullens, Bradley A; Baldet, Thierry; Goldarazena, Arturo

    2013-01-16

    months, whereas increased captures in autumn were noticed only in light traps. Both trapping systems failed to collect adult Culicoides midges in the coldest months of December, January and February. The literature on immature habitats of species suspected in BTV transmission in Europe, the Pulicaris group and particularly the Obsoletus group, is briefly reviewed. PMID:22999100

  7. Range expansion of the Bluetongue vector, Culicoides imicola, in continental France likely due to rare wind-transport events

    PubMed Central

    Jacquet, Stéphanie; Huber, Karine; Pagès, Nonito; Talavera, Sandra; Burgin, Laura E.; Carpenter, Simon; Sanders, Christopher; Dicko, Ahmadou H.; Djerbal, Mouloud; Goffredo, Maria; Lhor, Youssef; Lucientes, Javier; Miranda-Chueca, Miguel A.; Pereira Da Fonseca, Isabel; Ramilo, David W.; Setier-Rio, Marie-Laure; Bouyer, Jérémy; Chevillon, Christine; Balenghien, Thomas; Guis, Hélène; Garros, Claire

    2016-01-01

    The role of the northward expansion of Culicoides imicola Kieffer in recent and unprecedented outbreaks of Culicoides-borne arboviruses in southern Europe has been a significant point of contention. We combined entomological surveys, movement simulations of air-borne particles, and population genetics to reconstruct the chain of events that led to a newly colonized French area nestled at the northern foot of the Pyrenees. Simulating the movement of air-borne particles evidenced frequent wind-transport events allowing, within at most 36 hours, the immigration of midges from north-eastern Spain and Balearic Islands, and, as rare events, their immigration from Corsica. Completing the puzzle, population genetic analyses discriminated Corsica as the origin of the new population and identified two successive colonization events within west-Mediterranean basin. Our findings are of considerable importance when trying to understand the invasion of new territories by expanding species. PMID:27263862

  8. Range expansion of the Bluetongue vector, Culicoides imicola, in continental France likely due to rare wind-transport events.

    PubMed

    Jacquet, Stéphanie; Huber, Karine; Pagès, Nonito; Talavera, Sandra; Burgin, Laura E; Carpenter, Simon; Sanders, Christopher; Dicko, Ahmadou H; Djerbal, Mouloud; Goffredo, Maria; Lhor, Youssef; Lucientes, Javier; Miranda-Chueca, Miguel A; Pereira Da Fonseca, Isabel; Ramilo, David W; Setier-Rio, Marie-Laure; Bouyer, Jérémy; Chevillon, Christine; Balenghien, Thomas; Guis, Hélène; Garros, Claire

    2016-01-01

    The role of the northward expansion of Culicoides imicola Kieffer in recent and unprecedented outbreaks of Culicoides-borne arboviruses in southern Europe has been a significant point of contention. We combined entomological surveys, movement simulations of air-borne particles, and population genetics to reconstruct the chain of events that led to a newly colonized French area nestled at the northern foot of the Pyrenees. Simulating the movement of air-borne particles evidenced frequent wind-transport events allowing, within at most 36 hours, the immigration of midges from north-eastern Spain and Balearic Islands, and, as rare events, their immigration from Corsica. Completing the puzzle, population genetic analyses discriminated Corsica as the origin of the new population and identified two successive colonization events within west-Mediterranean basin. Our findings are of considerable importance when trying to understand the invasion of new territories by expanding species. PMID:27263862

  9. In Situ Immune Infrared Fluorescent Staining for Detection and Quantification of Bluetongue Virus in Cullicoides Insect Cell Culture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bluetongue virus (BTV) is transmitted to sheep, cattle and other ruminants by Culicoides spp. of biting midges. Cell lines have been developed from C. sonorensis; however, techniques for directly detecting and quantifying virus in these insect cells are lacking. In situ immune infrared fluorescent s...

  10. In situ immune infrared fluorescent staining for detection and quantification of bluetongue virus in insect cell culture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bluetongue virus (BTV) is transmitted to sheep, cattle and other ruminants by Culicoides spp. of biting midges. Cell lines developed from C. sonorensis have facilitated studies of virus replication and the role of the insect vector in BTV transmission. However, techniques for directly detecting viru...

  11. Biting rates and developmental substrates for biting midges (Diptera: Ceratopogonidae) in Iquitos, Peru.

    PubMed

    Mercer, David R; Spinelli, Gustavo R; Watts, Douglas M; Tesh, Robert B

    2003-11-01

    Biting midges (Diptera: Ceratopogonidae) were collected at 16 periurban and rural sites around Iquitos, Peru, between 17 October 1996 and 26 May 1997. Culicoides paraensis (Goeldi), the principal vector of Oropouche virus, was the most commonly collected species (9,086 flies) with Culicoides insinuatus Wirth & Blanton second (7,229 flies). Although both species were collected at all sampling sites (linear (distance surveyed approximately 25 km), C. paraensis dominated at northern collection sites (> 90%), whereas C. insinuatus prevailed at southern collection sites (> 60%). C. paraensis were collected from human sentinels at a constant rate throughout daylight hours, at similar rates during wet and dry months, and regardless of rainfall. Larval developmental substrates for C. paraensis included decaying platano (Musa x paradisiaca L. [Musaceae]) stems, stumps, flowers, fruits, and debris beneath platano trees as well as from soil beneath a fruiting mamay (Syzygium malaccense Merr. & Perry [Myrtaceae] ) tree and organic-rich mud along a lake shoreline. C. insinuatus adults likewise emerged from decaying platano and organic-rich mud along a lake shoreline, but also from debris accumulated in the axils of aguaje (Mauritia flexuosa L. [Palmae]) fronds and decaying citrus fruit. Despite high numbers of biting adults near putative substrates, adults of neither species emerged from other decomposing plant material, soil, phytotelmata, or artificial containers. Because both species of biting midges emerged in high numbers from all parts of platano (ubiquitous in Iquitos), it will be challenging to control them through sanitation. PMID:14765657

  12. Changes in relative species compositions of biting midges (Diptera: Ceratopogonidae) and an outbreak of Oropouche virus in Iquitos, Peru.

    PubMed

    Mercer, David R; Castillo-Pizango, Maikol J

    2005-07-01

    Species compositions of Culicoides paraensis (Goeldi) (Diptera: Ceratopogonidae), the major vector of Oropouche virus to humans in Central and South American urban cycles, and Culicoides insinuatus Ortiz & Leon differed along a northeast-to-southwest transect across Iquitos, Department of Loreto, Peru. The relative distributions of the species were consistent with patterns of human outbreaks along the Amazon River. We resumed collection of biting midges between May 2000 and January 2004 at three sites previously sampled (1996 -1997) to determine whether the known vector was expanding its range relative to the earlier survey. C. paraensis did not replace C. insinuatus across the region surveyed. Instead, C. insinuatus dominated the more southern sites and significantly increased its relative proportion at all three sites. Apparently, microhabitat differences and not range expansion by C. paraensis were responsible for differences in species compositions across the sample sites. PMID:16119543

  13. Screening of Oomycete Fungi for Their Potential Role in Reducing the Biting Midge (Diptera: Ceratopogonidae) Larval Populations in Hervey Bay, Queensland, Australia

    PubMed Central

    Stephen, Kirsty; Kurtböke, D. Ipek

    2011-01-01

    Biting midges are globally distributed pests causing significant economic losses and transmitting arbovirus diseases to both animals and humans. Current biological and chemical control strategies for biting midge target destruction of adult forms, but strategies directed at immature stages of the insect have yet to be explored in Australia. In the present study, coastal waters of Hervey Bay region in Queensland, Australia were screened to detect the habitats of biting midge at immature stages. These results were then correlated to local environmental conditions and naturally occurring entomopathogenic fungal flora, in particular the Oomycete fungi, to determine their reducing effect on insect immature stages in the search for biological control agents in the region. The dominant species of biting midge found within this study was Culicoides subimmaculatus occuring between mean high water neaps and mean high water spring tide levels. Within this intertidal zone, the presence of C. subimmaculatus larvae was found to be influenced by both sediment size and distance from shore. Halophytophthora isolates colonized both dead and alive pupae. However, the association was found to be surface colonization rather than invasion causing the death of the host. Lack of aggressive oomycete fungal antagonists towards midge larvae might correlate with increased incidences of biting midge infestations in the region. PMID:21655137

  14. Circadian activity of Culicoides oxystoma (Diptera: Ceratopogonidae), potential vector of bluetongue and African horse sickness viruses in the Niayes area, Senegal.

    PubMed

    Fall, Moussa; Fall, Assane G; Seck, Momar T; Bouyer, Jérémy; Diarra, Maryam; Balenghien, Thomas; Garros, Claire; Bakhoum, Mame T; Faye, Ousmane; Baldet, Thierry; Gimonneau, Geoffrey

    2015-08-01

    Culicoides biting midges (Diptera: Ceratopogonidae) are important vectors of arboviruses in Africa. Culicoides oxystoma has been recently recorded in the Niayes region of Senegal (West Africa) and its high abundance on horses suggests a potential implication in the transmission of the African horse sickness virus in this region. This species is also suspected to transmit bluetongue virus to imported breeds of sheep. Little information is available on the biology and ecology of Culicoides in Africa. Therefore, understanding the circadian host-seeking activity of this putative vector is of primary importance to assess the risk of the transmission of Culicoides-borne pathogens. To achieve this objective, midges were collected using a sheep-baited trap over two consecutive 24-h periods during four seasons in 2012. A total of 441 Culicoides, belonging to nine species including 418 (94.8%) specimens of C. oxystoma, were collected. C. oxystoma presented a bimodal circadian host-seeking activity at sunrise and sunset in July and was active 3 h after sunrise in April. Daily activity appeared mainly related to time periods. Morning activity increased with the increasing temperature up to about 27 °C and then decreased with the decreasing humidity, suggesting thermal limits for C. oxystoma activity. Evening activity increased with the increasing humidity and the decreasing temperature, comprised between 20 and 27 °C according to seasons. Interestingly, males were more abundant in our sampling sessions, with similar activity periods than females, suggesting potential animal host implication in the facilitation of reproduction. Finally, the low number of C. oxystoma collected render practical vector-control recommendations difficult to provide and highlight the lack of knowledge on the bio-ecology of this species of veterinary interest. PMID:26002826

  15. Faustovirus-Like Asfarvirus in Hematophagous Biting Midges and Their Vertebrate Hosts

    PubMed Central

    Temmam, Sarah; Monteil-Bouchard, Sonia; Sambou, Masse; Aubadie-Ladrix, Maxence; Azza, Saïd; Decloquement, Philippe; Khalil, Jacques Y. Bou; Baudoin, Jean-Pierre; Jardot, Priscilla; Robert, Catherine; La Scola, Bernard; Mediannikov, Oleg Y.; Raoult, Didier; Desnues, Christelle

    2015-01-01

    Faustovirus, a new Asfarviridae-related giant virus, was recently isolated in Vermamoeba vermiformis, a protist found in sewage water in various geographical locations and occasionally reported in human eye infection cases. As part of a global metagenomic analysis of viral communities existing in biting midges, we report here for the first time the identification and isolation of a Faustovirus-like virus in hematophagous arthropods and its detection in their animal hosts. The DNA virome analysis of three pools of Culicoides sp., engorged female Culicoides imicola and non-engorged male/female C. imicola biting midges collected in Senegal, revealed the presence of amoeba-infecting giant viruses and, among them, a majority of sequences related to Faustovirus. Phylogenetic analyses conducted on several structural genes of Faustovirus confirmed the clustering of the arthropod-borne Faustovirus with sewage-borne Faustoviruses, with a distinct geographical clustering of Senegalese Faustovirus strains. Transmission electron microscopy identified viral particles with morphologies and diameters which were compatible with Faustovirus. The presence of infectious arthropod-borne Faustovirus was finally confirmed by successful isolation on V. vermiformis amoeba. Global proteomic analysis of biting midges identified that arthropods' blood meal originating from cattle, rodents and humans. Further screening of cattle sera and rodent tissue resulted in prevalence of Faustovirus being estimated at 38% in rodents and 14% in cattle, suggesting a possible origin of Faustovirus presence in arthropods via the ingestion of contaminated blood meal. Viral loads were the highest in rodents' urine and kidney samples, suggesting a possible excretion of viral particles into the environment. Faustovirus DNA polymerase-related sequences were also detected in more than 9 and 11% of febrile patients and healthy Senegalese human sera, respectively. Our study thus, highlights the need to investigate

  16. Faustovirus-Like Asfarvirus in Hematophagous Biting Midges and Their Vertebrate Hosts.

    PubMed

    Temmam, Sarah; Monteil-Bouchard, Sonia; Sambou, Masse; Aubadie-Ladrix, Maxence; Azza, Saïd; Decloquement, Philippe; Khalil, Jacques Y Bou; Baudoin, Jean-Pierre; Jardot, Priscilla; Robert, Catherine; La Scola, Bernard; Mediannikov, Oleg Y; Raoult, Didier; Desnues, Christelle

    2015-01-01

    Faustovirus, a new Asfarviridae-related giant virus, was recently isolated in Vermamoeba vermiformis, a protist found in sewage water in various geographical locations and occasionally reported in human eye infection cases. As part of a global metagenomic analysis of viral communities existing in biting midges, we report here for the first time the identification and isolation of a Faustovirus-like virus in hematophagous arthropods and its detection in their animal hosts. The DNA virome analysis of three pools of Culicoides sp., engorged female Culicoides imicola and non-engorged male/female C. imicola biting midges collected in Senegal, revealed the presence of amoeba-infecting giant viruses and, among them, a majority of sequences related to Faustovirus. Phylogenetic analyses conducted on several structural genes of Faustovirus confirmed the clustering of the arthropod-borne Faustovirus with sewage-borne Faustoviruses, with a distinct geographical clustering of Senegalese Faustovirus strains. Transmission electron microscopy identified viral particles with morphologies and diameters which were compatible with Faustovirus. The presence of infectious arthropod-borne Faustovirus was finally confirmed by successful isolation on V. vermiformis amoeba. Global proteomic analysis of biting midges identified that arthropods' blood meal originating from cattle, rodents and humans. Further screening of cattle sera and rodent tissue resulted in prevalence of Faustovirus being estimated at 38% in rodents and 14% in cattle, suggesting a possible origin of Faustovirus presence in arthropods via the ingestion of contaminated blood meal. Viral loads were the highest in rodents' urine and kidney samples, suggesting a possible excretion of viral particles into the environment. Faustovirus DNA polymerase-related sequences were also detected in more than 9 and 11% of febrile patients and healthy Senegalese human sera, respectively. Our study thus, highlights the need to investigate

  17. Spatial and Temporal Distribution of Culicoides Species in Mainland Portugal (2005–2010). Results of the Portuguese Entomological Surveillance Programme

    PubMed Central

    Ramilo, David W.; Amador, Rita; Madeira, Sara; Baptista, Filipa M.; Harrup, Lara E.; Lucientes, Javier; Boinas, Fernando

    2015-01-01

    Bluetongue virus (BTV) is transmitted by Culicoides biting midges and causes an infectious, non-contagious disease of ruminants. It has been rapidly emerging in southern Europe since 1998. In mainland Portugal, strains of BTV belonging to three serotypes have been detected: BTV-10 (1956-1960), BTV-4 (2004-2006 and 2013) and BTV-1 (2007-2012). This paper describes the design, implementation and results of the Entomological Surveillance Programme covering mainland Portugal, between 2005 and 2010, including 5,650 caches. Culicoides imicola Kieffer was mostly found in central and southern regions of Portugal, although it was sporadically detected in northern latitudes. Its peak activity occurred in the autumn and it was active during the winter months in limited areas of the country. Obsoletus group was present at the highest densities in the north although they were found throughout the country in substantial numbers. Culicoides activity occurred all year round but peaked in the spring. A generalized linear mixed model was developed for the analysis of the environmental factors associated with activity of the species of Culicoides suspected vectors of BTV in the country. For C. imicola Kieffer, the most important variables were month, diurnal temperature range (DTR), the number of frost days (FRS) and median monthly temperature (TMP). For the Obsoletus group, the most important factors were month, diurnal temperature range (DTR), and linear and quadratic terms for median monthly temperature (TMP). The results reported can improve our understanding of climatic factors in Culicoides activity influencing their distribution and seasonal pattern. PMID:25906151

  18. To bite or not to bite! A questionnaire-based survey assessing why some people are bitten more than others by midges

    PubMed Central

    2010-01-01

    Background The Scottish biting midge, Culicoides impunctatus, responsible for more than 90% of biting attacks on human beings in Scotland, is known to demonstrate a preference for certain human hosts over others. Methods In this study we used a questionnaire-based survey to assess the association between people's perception of how badly they get bitten by midges and their demographic, lifestyle and health related characteristics. Results Most people (85.8%) reported being bitten sometimes, often or always with only 14.2% reporting never being bitten by midges when in Scotland. There was no association between level of bites received and age, smoking, diet, exercise, medication, eating strongly flavoured foods or alcohol consumption. However, there was a strong association between the probability of being bitten and increasing height (in men) and BMI (in women). A large proportion of participants (33.8%) reported experiencing a bad/severe reaction to midge bites while 53.1% reported a minor reaction and 13.1% no reaction at all. Also, women tend to react more than men to midge bites. Additionally, the results indicated that the susceptibility to being bitten by midges is hereditary. Conclusions This study suggests that midges prefer to bite men that are tall and women that have a large BMI, and that the tendency for a child to be bitten or not could be inherited from their parent. The study is questionnaire-based; therefore, the interpretation of the results may be limited by the subjectivity of the answers given by the respondents. Although the results are relevant only to the Scottish biting midge, the approach used here could be useful for investigating human-insect interactions for other insects, particularly those which transmit pathogens that cause disease. PMID:20500852

  19. Bioscouring of cotton using lipase from marine bacteria Bacillus sonorensis.

    PubMed

    Nerurkar, Madhura; Joshi, Manasi; Adivarekar, Ravindra

    2015-01-01

    Bioscouring refers to the enzymatic removal of impurities from cotton fabric, which imparts it with improved hydrophilicity for further wet processes. In the present study, the efficacy of lipase from newly isolated marine bacteria Bacillus sonorensis isolated from marine clams Paphia malabarica collected from Kalbadevi estuary, Mumbai, India, has been evaluated for scouring of cotton fabric and compared with conventional alkaline scouring of cotton. As a scouring agent for cotton fabrics, the lipase from B. sonorensis was capable of removing substantial amount of wax from the cotton surface and hydrolyzing it into fatty acids. Bioscouring carried out with lipase at a concentration of 8 % on the weight of the fabric (owf) at pH 9, temperature 60 °C for 120 min showed maximum weight loss and hydrophilicity. The Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) studies revealed that the lipase-scoured fabric showed smooth surface indicating no damage to the fabric whereas the surface of the alkaline-scoured fabric appeared rough causing damage to the fabric. Evaluation of fabric properties such as wettability, whiteness, dyeing behaviour, tensile strength and bending rigidity revealed that the bioscouring using lipase from B. sonorensis is as effective as conventional alkaline treatment. PMID:25256798

  20. Climate change: effects on culicoides--transmitted viruses and implications for the UK.

    PubMed

    Wittmann, E J; Baylis, M

    2000-09-01

    Changes in the distribution and abundance of insects are likely to be amongst the most important and immediate effects of climate change. We review here the risk that climate change poses to the UK's livestock industry via effects on Culicoides biting midges, the vectors of several arboviruses, including those that cause bluetongue (BT) and African horse sickness (AHS). The major old-world vector of BT and AHS viruses, C. imicola, occurs in southern Europe and will spread further north as global temperatures increase. It is unlikely, however, that in the foreseeable future it will reach and become established in the UK. As the distribution of C. imicola moves north, however, it may bring BT and AHS viruses into the range of other Culicoides species that are known to be competent vectors and which occur much further north. Once infected via this 'baton effect', these species may be able to spread the viruses over much of Europe, including the UK. Climate change may increase their vector competence further and will also increase the likelihood of viruses surviving from one year to the next. An additional risk is that the predicted increase in the frequency of short periods of hot temperatures may lead to the creation of novel vector species, by removing the barriers that in colder conditions make them refractory to viral infection. PMID:10985802

  1. Prevalence of different species of Culicoides in Bangalore rural and urban districts of South India.

    PubMed

    Archana, M; D'Souza, Placid E; Renuka Prasad, C; Byregowda, S M

    2016-09-01

    A study was conducted to observe the prevalence of Culicoides a biting midge, important pest and prime vector for various viruses, protozoa and filarid worms. In the vicinity of 11 different farms of cattle, buffalo, sheep and goats in Bangalore rural and urban districts the flies were collected by using UV traps (Onderstepoort Veterinary Institute. ARC. LNR) connected with suction fan for the period of 1 year (2012-2013). Around 83,629 Culicoides were collected of which 77,906 (93.16 %) were female and 5,723 (6.84 %) were males and 40,120 (47.97 %) of C. imicola, 39,366 (47.07 %) C. oxystoma, 2,504 (2.99 %) C. actoni, 1,145 (1.37 %) C. peregrinus, 145 (0.17 %) C. huffi, 120 (0.16 %) C. innoxius, 90 (0.11 %) C. palpifer, 67 (0.08 %) C. anopheles, 37 (0.04 %) C. circumscriptus and 25 (0.03 %) were C. arakawae. It was observed that C. imicola and C. oxystoma were the most predominant species prevalent in Bangalore rural and urban districts of Karnataka. PMID:27605753

  2. A new algorithm quantifies the roles of wind and midge flight activity in the bluetongue epizootic in northwest Europe.

    PubMed

    Sedda, Luigi; Brown, Heidi E; Purse, Bethan V; Burgin, Laura; Gloster, John; Rogers, David J

    2012-06-22

    The 2006 bluetongue (BT) outbreak in northwestern Europe had devastating effects on cattle and sheep in that intensively farmed area. The role of wind in disease spread, through its effect on Culicoides dispersal, is still uncertain, and remains unquantified. We examine here the relationship between farm-level infection dates and wind speed and direction within the framework of a novel model involving both mechanistic and stochastic steps. We consider wind as both a carrier of host semio-chemicals, to which midges might respond by upwind flight, and as a transporter of the midges themselves, in a more or less downwind direction. For completeness, we also consider midge movement independent of wind and various combinations of upwind, downwind and random movements. Using stochastic simulation, we are able to explain infection onset at 94 per cent of the 2025 affected farms. We conclude that 54 per cent of outbreaks occurred through (presumably midge) movement of infections over distances of no more than 5 km, 92 per cent over distances of no more than 31 km and only 2 per cent over any greater distances. The modal value for all infections combined is less than 1 km. Our analysis suggests that previous claims for a higher frequency of long-distance infections are unfounded. We suggest that many apparent long-distance infections resulted from sequences of shorter-range infections; a 'stepping stone' effect. Our analysis also found that downwind movement (the only sort so far considered in explanations of BT epidemics) is responsible for only 39 per cent of all infections, and highlights the effective contribution to disease spread of upwind midge movement, which accounted for 38 per cent of all infections. The importance of midge flight speed is also investigated. Within the same model framework, lower midge active flight speed (of 0.13 rather than 0.5 m s(-1)) reduced virtually to zero the role of upwind movement, mainly because modelled wind speeds in the area

  3. First occurrence of Culicoides obsoletus-transmitted Bluetongue virus epidemic in Central Europe.

    PubMed

    Mehlhorn, Heinz; Walldorf, Volker; Klimpel, Sven; Jahn, Birgit; Jaeger, Friedhelm; Eschweiler, Josef; Hoffmann, Bernd; Beer, Martin

    2007-06-01

    In August 2006, Bluetongue virus disease (BTD) was detected for the first time in the Netherlands, Belgium, Germany and Northern France. Serological tests as well as reverse transcriptase polymerase chain reaction (RT-PCR) proved the occurrence of Bluetongue virus (BTV) in diseased sheep and cattle, and the virus was identified as serotype 8. Therefore, the search for possible vectors was immediately initiated in the outbreak region in Germany. Traps with automatically regulated ultraviolet light lamps were placed at two different farms with sero-positive cattle, and insect monitoring was done from August 2006 until January 2007. The caught arthropods were weekly determined, and it could be observed that midges of the dipteran family Ceratopogonidae occurred in large numbers, sometimes representing up to 40% of all individuals. The microscopical analysis of the wing morphology showed that the species (complex) Culicoides obsoletus was most abundant covering about 97% of the analysed midges. On the second place ranged C. pulicaris, while C. nubeculosus and C. festivipennis were found only as single individuals. Fed and unfed females were separated, sent to the National Reference Laboratory for Bluetongue disease (Friedrich-Loeffler-Institut, Isle of Riems, Germany) and investigated with a BTV-8-specific real-time RT-PCR. It could be demonstrated that at both farms both fed and unfed C. obsoletus were tested positive for BTV-8 genomes, while none of the other species scored positive. This finding strongly supports that the BTD-epidemic, which reached in the meantime wide regions of North Rhine-Westphalia in Germany and of the neighbouring countries with several hundreds of affected farms, is initiated by virus transmission during the blood meal of midges of the C. obsoletus complex. Since they were captured still at the 21st of December close to cattle with clinical signs, it must be feared that BTV-8 is now established in Central Europe, where it had been absent

  4. Pest management update on sunflower midge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The sunflower midge (Contarinia schulzi) is a serious insect pest of sunflower, causing bud and head deformation that lead to poor seed development, and in many cases no seed development. This presentation describes the life cycle of the sunflower midge and shows images of infested sunflower heads. ...

  5. Gall midges (hessian flies) as plant pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gall midges constitute an important group of plant-parasitic insects. The Hessian fly (HF, Mayetiola destructor), the most investigated gall midge, was the first insect hypothesized to have a gene-for-gene interaction with its host plant, wheat (Triticum spp.). Recent investigations support that h...

  6. Effect of Culicoides Sonorensis Salivary Proteins on Clinical Disease Outcome in Experimental Bluetongue Virus Serotype 8 Infection of Dorset Sheep

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bluetongue is an insect-transmitted disease of domestic and wild ruminants. In the U.S., sheep are the most susceptible livestock species. Severity and form of clinical disease varies greatly depending on the outbreak serotype or specific strain within a serotype. To predict disease risk from any of...

  7. Culicoides Species Communities Associated with Wild Ruminant Ecosystems in Spain: Tracking the Way to Determine Potential Bridge Vectors for Arboviruses

    PubMed Central

    Talavera, Sandra; Muñoz-Muñoz, Francesc; Durán, Mauricio; Verdún, Marta; Soler-Membrives, Anna; Oleaga, Álvaro; Arenas, Antonio; Ruiz-Fons, Francisco; Estrada, Rosa; Pagès, Nitu

    2015-01-01

    The genus Culicoides Latreille 1809 is a well-known vector for protozoa, filarial worms and, above all, numerous viruses. The Bluetongue virus (BTV) and the recently emerged Schmallenberg virus (SBV) are responsible for important infectious, non-contagious, insect-borne viral diseases found in domestic ruminants and transmitted by Culicoides spp. Both of these diseases have been detected in wild ruminants, but their role as reservoirs during the vector-free season still remains relatively unknown. In fact, we tend to ignore the possibility of wild ruminants acting as a source of disease (BTV, SBV) and permitting its reintroduction to domestic ruminants during the following vector season. In this context, a knowledge of the composition of the Culicoides species communities that inhabit areas where there are wild ruminants is of major importance as the presence of a vector species is a prerequisite for disease transmission. In this study, samplings were conducted in areas inhabited by different wild ruminant species; samples were taken in both 2009 and 2010, on a monthly basis, during the peak season for midge activity (in summer and autumn). A total of 102,693 specimens of 40 different species of the genus Culicoides were trapped; these included major BTV and SBV vector species. The most abundant vector species were C. imicola and species of the Obsoletus group, which represented 15% and 11% of total numbers of specimens, respectively. At the local scale, the presence of major BTV and SBV vector species in areas with wild ruminants coincided with that of the nearest sentinel farms included in the Spanish Bluetongue Entomological Surveillance Programme, although their relative abundance varied. The data suggest that such species do not exhibit strong host specificity towards either domestic or wild ruminants and that they could consequently play a prominent role as bridge vectors for different pathogens between both types of ruminants. This finding would support the

  8. Models for the dispersal in Australia of the arbovirus vector, Culicoides brevitarsis Kieffer (Diptera: Ceratopogonidae).

    PubMed

    Bishop, A L; Barchia, I M; Spohr, L J

    2000-12-01

    Culicoides brevitarsis is the main biting midge responsible for the transmission of bluetongue and Akabane viruses to livestock in Australia. Models are given for its dispersal after winter from endemic areas at the southern limit of its distribution in New South Wales (NSW); the models might also be applicable elsewhere. Model 1 shows that dispersal can be explained by distance from a key point just outside the endemic area in mid-northern/northern coastal NSW. The model provides probability data for times of first occurrence at sites within regions down the southern coastal plain or up the Hunter Valley towards (but rarely reaching) the western slopes and tablelands. Model 2 shows that the movement depends on temperature and wind speed from northerly and easterly directions. Preliminary data also are given to suggest a relationship between density in the endemic area and the maximum distance that C. brevitarsis can travel in a given year. The models can be linked to other information which in combination can provide probabilities for winter survival outside the endemic area, times of occurrence at sites where it cannot survive winter and times when activity ceases naturally at these sites at the end of the season. This information can be used to predict the potential for virus transmission and indicate zones of seasonal freedom from both vector and virus for the export of livestock. PMID:11087955

  9. Regulation of Heliothis virescens Innate Immune Responses to the Endoparasitoid Campoletis sonorensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect immune responses play important roles in host defense against pathogens and parasitoids. In this study, we propose that the regulation of host immune responses may determine the successful parasitization of Campoletis sonorensis in the host. To investigate the regulation of innate immune resp...

  10. New records of Culicoides species (Diptera: Ceratopogonidae) for Bolivia.

    PubMed

    Aybar, Cecilia A Veggiani; Juri, María J Dantur; de Grosso, Mercedes S Lizarralde; Spinell, Gustavo R

    2011-09-01

    Culicoides debilipalpis, C insignis, C. lahillei, and C venezuelensis are reported for the first time for Bolivia. The geographical distribution of C. paraensis extends to the Tarija Department. PMID:22017095

  11. Biting midges (Diptera: Ceratopogonidae) from Martín García Island, Argentina.

    PubMed

    Ronderos, María M; Marino, Pablo I; Díaz, Florentina; Estévez, Ana L

    2011-09-01

    Nearly 230 species of biting midges have been recorded or described from Argentina; 38 of them are known from the Buenos Aires province and only one is cited from Martín García Island. This paper presents the results raised from six collecting trips which took place on the island during spring 2005, summer 2006 and autumn 2009. Diverse sampling sites including permanent and temporary aquatic environments were chosen, most of the ten sampling sites were ponds of diverse origin, some of these environments were covered with floating vegetation as Lemna gibba, Lemna minuscule, Salvinia biloba, Salvinia minima, Azolla filiculoides, Limnobium laevigatum, Pistia stratiotes, Spirodela intermedia, Wolffiella oblonga and Wolffia columbiana. Other sites were placed in urban and suburban areas. Adults were collected with sweep nets at sunrise and sunset and with light traps at intervals of four to five hours at night, depending on electricity availability on the island. Larvae and pupae were collected with different implements depending on characteristics of each surveyed aquatic habitat. In free standing water, they were captured with small sieves or hand pipettes and micropipettes, flotation techniques were utilized for sampling vegetated areas, free and rooted floating hydrophytes were extracted for removing insects among them. Thirteen species of Ceratopogonidae were collected, three of Atrichopogon Kieffer, three of Forcipomyia Meigen, two of Dasyhelea Kieffer, four of Culicoides Latreille, and one of Bezzia Kieffer, all representing new records from the island. PMID:22017124

  12. EVALUATION OF TWO COMMERCIAL TRAPS FOR THE COLLECTION OF CULICOIDES (DIPTERA: CERATOPOGONIDAE)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two types of commercial propane-powered traps, Mosquito Magnet Freedom (Freedom), and Mosquito Magnet Liberty Plus (Liberty Plus), were evaluated in Cedar Key, FL for the collection of Culicoides. Trap preference and seasonal characteristics for three major species, Culicoides furens, Culicoides bar...

  13. Culicoides aspirated from cattle in Costa Rica, Honduras, Panama and Puerto Rico, and their role as potential vectors of bluetongue viruses. Regional Bluetongue Team.

    PubMed

    Sáenz, M R; Greiner, E C

    1994-01-01

    In 1991, as part of an epidemiological study of bluetongue viruses (BTV) in the Central American and Caribbean region, eight farms located in Costa Rica, Honduras, Panamá and Puerto Rico were sampled for Culicoides spp. attacking cattle. Using cattle bait, 3884 biting midges were collected with an electric aspirator during both crepuscular periods. The predominant species captured was Culicoides insignis Lutz (95%), followed by C.furens (Poey) (3.4%), C.filarifer Hoffman/C.ocumarensis Ortiz (0.9%), C.lahillei (Iches) (0.7%), C.arubae Fox and Hoffman (< 0.1%) and C.gorgasi Wirth and Blanton (< 0.1%). Blood-engorged specimens from some of these species were collected and comprised: 18% of all C.insignis, 36% of C.furens, 37% of filarifer/ocumarensis and 25% of C.lahillei. No engorged C.arubae or C.gorgasi were caught. These results confirm earlier findings pointing to C.insignis, C.furens and C.filarifer/ocumarensis as potential vectors of BTV in the region. PMID:8161838

  14. Draft Whole-Genome Sequence of Bacillus sonorensis Strain L12, a Source of Nonribosomal Lipopeptides.

    PubMed

    Adimpong, David B; Sørensen, Kim I; Nielsen, Dennis S; Thorsen, Line; Rasmussen, Thomas B; Derkx, Patrick M F; Jespersen, Lene

    2013-01-01

    The Bacillus sonorensis L12 draft genome sequence is approximately 4,647,754 bp in size with a G+C content of 45.2%. Over 86% of the genome contains protein-encoding genes, including several gene clusters for de novo biosynthesis of the nonribosomal lipopeptides iturin, bacitracin, and fengycin, which could mean that the strain exhibits antifungal effects. PMID:23538904

  15. Sugar-feeding status alters biting midge photoattraction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biting midges transmit disease in livestock and wildlife that result in significant loss of value. Therefore understanding biting midge attraction to light is important for monitoring the insect populations and possibly using traps to reduce populations. This study determined that color of light is ...

  16. Identification of human-derived volatile chemicals that interfere with attraction of the Scottish biting midge and their potential use as repellents.

    PubMed

    Logan, James G; Seal, Nicola J; Cook, James I; Stanczyk, Nina M; Birkett, Michael A; Clark, Suzanne J; Gezan, Salvador A; Wadhams, Lester J; Pickett, John A; Mordue, A Jennifer

    2009-03-01

    The Scottish biting midge, Culicoides impunctatus (Diptera: Ceratopogonidae), is a major pest in Scotland, causing a significant impact to the Scottish tourist and forestry industries. C. impunctatus is a generalist feeder, preferring to feed on large mammals, and is notorious for its attacks on humans. Until now, there was anecdotal evidence for differential attraction of female host-seeking C. impunctatus to individual human hosts, and the mechanism for this phenomenon was unknown. Using extracts of human odor collected by air entrainment, electroantennogram recordings to identify the physiologically active components, followed by behavioral assays, we show, for the first time, the differential attraction of female C. impunctatus to human odors and the chemical basis for this phenomenon. Certain chemicals, found in greater amounts in extracts that cause low attractiveness to midges, elicit a repellent effect in laboratory assays and repellency trials in the field. Differences in the production of these natural human-derived compounds could help to explain differential "attractiveness" between different human hosts. A mixture of two compounds in particular, 6-methyl-5-hepten-2-one and geranylacetone [(E)-6,10-dimethylundeca-5,9-dien-2-one], showed significant repellency (87, 77.4, 74.2, and 31.6% at hours 0, 1, 2, and 3, respectively) in the field and have the potential to be developed as novel repellents. PMID:19351071

  17. Worldwide niche and future potential distribution of Culicoides imicola, a major vector of bluetongue and African horse sickness viruses.

    PubMed

    Guichard, Sylvain; Guis, Hélène; Tran, Annelise; Garros, Claire; Balenghien, Thomas; Kriticos, Darren J

    2014-01-01

    We modelled the ecoclimatic niche of Culicoides imicola, a major arthropod vector of midge-borne viral pathogens affecting ruminants and equids, at fine scale and on a global extent, so as to provide insight into current and future risks of disease epizootics, and increase current knowledge of the species' ecology. Based on the known distribution and ecology of C. imicola, the species' response to monthly climatic conditions was characterised using CLIMEX with 10' spatial resolution climatic datasets. The species' climatic niche was projected worldwide and under future climatic scenarios. The validated model highlights the role of irrigation in supporting the occurrence of C. imicola in arid regions. In Europe, the modelled potential distribution of C. imicola extended further West than its reported distribution, raising questions regarding ongoing process of colonization and non-climatic habitat factors. The CLIMEX model highlighted similar ecological niches for C. imicola and the Australasian C. brevitarsis raising questions on biogeography and biosecurity. Under the climate change scenarios considered, its' modelled potential distribution could expand northward in the Northern hemisphere, whereas in Africa its range may contract in the future. The biosecurity risks from bluetongue and African horse sickness viruses need to be re-evaluated in regions where the vector's niche is suitable. Under a warmer climate, the risk of vector-borne epizootic pathogens such as bluetongue and African horse sickness viruses are likely to increase as the climate suitability for C. imicola shifts poleward, especially in Western Europe. PMID:25391148

  18. Worldwide Niche and Future Potential Distribution of Culicoides imicola, a Major Vector of Bluetongue and African Horse Sickness Viruses

    PubMed Central

    Guichard, Sylvain; Guis, Hélène; Tran, Annelise; Garros, Claire; Balenghien, Thomas; Kriticos, Darren J.

    2014-01-01

    We modelled the ecoclimatic niche of Culicoides imicola, a major arthropod vector of midge-borne viral pathogens affecting ruminants and equids, at fine scale and on a global extent, so as to provide insight into current and future risks of disease epizootics, and increase current knowledge of the species' ecology. Based on the known distribution and ecology of C. imicola, the species' response to monthly climatic conditions was characterised using CLIMEX with 10′ spatial resolution climatic datasets. The species' climatic niche was projected worldwide and under future climatic scenarios. The validated model highlights the role of irrigation in supporting the occurrence of C. imicola in arid regions. In Europe, the modelled potential distribution of C. imicola extended further West than its reported distribution, raising questions regarding ongoing process of colonization and non-climatic habitat factors. The CLIMEX model highlighted similar ecological niches for C. imicola and the Australasian C. brevitarsis raising questions on biogeography and biosecurity. Under the climate change scenarios considered, its' modelled potential distribution could expand northward in the Northern hemisphere, whereas in Africa its range may contract in the future. The biosecurity risks from bluetongue and African horse sickness viruses need to be re-evaluated in regions where the vector's niche is suitable. Under a warmer climate, the risk of vector-borne epizootic pathogens such as bluetongue and African horse sickness viruses are likely to increase as the climate suitability for C. imicola shifts poleward, especially in Western Europe. PMID:25391148

  19. Detection of Low-Level Cardinium and Wolbachia Infections in Culicoides

    PubMed Central

    Mee, Peter T.; Weeks, Andrew R.; Walker, Peter J.; Hoffmann, Ary A.

    2015-01-01

    Bacterial endosymbionts have been identified as potentially useful biological control agents for a range of invertebrate vectors of disease. Previous studies of Culicoides (Diptera: Ceratopogonidae) species using conventional PCR assays have provided evidence of Wolbachia (1/33) and Cardinium (8/33) infections. Here, we screened 20 species of Culicoides for Wolbachia and Cardinium, utilizing a combination of conventional PCR and more sensitive quantitative PCR (qPCR) assays. Low levels of Cardinium DNA were detected in females of all but one of the Culicoides species screened, and low levels of Wolbachia were detected in females of 9 of the 20 Culicoides species. Sequence analysis based on partial 16S rRNA gene and gyrB sequences identified “Candidatus Cardinium hertigii” from group C, which has previously been identified in Culicoides from Japan, Israel, and the United Kingdom. Wolbachia strains detected in this study showed 98 to 99% sequence identity to Wolbachia previously detected from Culicoides based on the 16S rRNA gene, whereas a strain with a novel wsp sequence was identified in Culicoides narrabeenensis. Cardinium isolates grouped to geographical regions independent of the host Culicoides species, suggesting possible geographical barriers to Cardinium movement. Screening also identified Asaia bacteria in Culicoides. These findings point to a diversity of low-level endosymbiont infections in Culicoides, providing candidates for further characterization and highlighting the widespread occurrence of these endosymbionts in this insect group. PMID:26150447

  20. Rice-gall midge interactions: Battle for survival.

    PubMed

    Bentur, Jagadish S; Rawat, Nidhi; Divya, D; Sinha, Deepak K; Agarrwal, Ruchi; Atray, Isha; Nair, Suresh

    2016-01-01

    Gall midges are insects specialized in maneuvering plant growth, metabolic and defense pathways for their benefit. The Asian rice gall midge and rice share such an intimate relationship that there is a constant battle for survival by either partner. Diverse responses by the rice host against the midge include necrotic hypersensitive resistance reaction, non-hypersensitive resistance reaction and gall-forming compatible interaction. Genetic studies have revealed that major R (resistance) genes confer resistance to gall midge in rice. Eleven gall midge R genes have been characterized so far in different rice varieties in India. In addition, no single R gene confers resistance against all the seven biotypes of the Asian rice gall midge, and none of the biotypes is virulent against all the resistance genes. Further, the interaction of the plant resistance gene with the insect avirulence gene is on a gene-for-gene basis. Our recent investigations involving suppressive subtraction hybridization cDNA libraries, microarray analyses, gene expression assays and metabolic profiling have revealed several molecular mechanisms, metabolite markers and pathways that are induced, down-regulated or altered in the rice host during incompatible or compatible interactions with the pest. This is also true for some of the pathways studied in the gall midge. Next generation sequencing technology, gene expression studies and conventional screening of gall midge cDNA libraries highlighted molecular approaches adopted by the insect to feed, survive and reproduce. This constant struggle by the midge to overcome the host defenses and the host to resist the pest has provided us with an opportunity to observe this battle for survival at the molecular level. PMID:26455891

  1. Comparison of emergence traps of different shape and translucency in the trapping of Culicoides (Diptera: Ceratopogonidae).

    PubMed

    Steinke, S; Lühken, R; Kroischke, F; Timmermann, E; Kiel, E

    2016-06-15

    Various types of emergence traps are available for investigations of the breeding habitats of Culicoides (Diptera: Ceratopogonidae). In order to assess the potential impact of the trap design on the trapping success, we compared the efficiency of opaque and white (more translucent) emergence traps and two trap shapes (cone-shaped and quadratic), to sample Culicoides emerging from cowpats. Significantly higher numbers of Culicoides chiopterus and Culicoides dewulfi were trapped with opaque traps, while there was no obvious effect of the trap shape. There were no distinct differences in the microclimate among different trap types. PMID:27198792

  2. The chemical ecology of cecidomyiid midges (Diptera: Cecidomyiidae).

    PubMed

    Hall, David R; Amarawardana, Lakmali; Cross, Jerry V; Francke, Wittko; Boddum, Tina; Hillbur, Ylva

    2012-01-01

    The family of cecidomyiid midges (Diptera: Cecidomyiidae) exhibits diversified patterns of life history, behavior, host range, population dynamics and other ecological traits. Those that feed on plants include many important agricultural pests; most cultivated plants are attacked by at least one midge species. Several features of the reproductive biology of cecidomyiid midges point to an important role for chemical communication, with this topic last reviewed comprehensively 12 years ago. Here, we review progress on identification of sex pheromones, chemicals involved in location of host plants, the neurophysiology of reception of volatile chemicals, and application of semiochemicals to management of pest species of cecidomyiid midges that has occurred during the last decade. We hope this review will stimulate and sustain further research in these fields. PMID:22215563

  3. The Hypersensitivity of Horses to Culicoides Bites in British Columbia

    PubMed Central

    Anderson, Gail S.; Belton, Peter; Kleider, Nicholas

    1988-01-01

    Culicoides hypersensitivity is a chronic, recurrent, seasonal dermatitis of horses that has a worldwide distribution, but has only recently been reported in Canada. It is characterized by intense pruritus resulting in lesions associated with self-induced trauma. A survey of veterinarians and horse-owners in British Columbia showed no differences in susceptibility due to the sex, color, breed, or height of the horses. The prevalence of the disease in the 209 horses surveyed was 26%. Horses sharing the same pasture could be unaffected. The disease was reported primarily from southwestern British Columbia; it occurred between April and October and usually affected the ventral midline, mane, and tail. Horses were generally less than nine years old when the clinical signs first appeared ([unk]=5.9 yr). Culicoides hypersensitivity was common in the lineage of several affected horses, possibly indicating a genetic susceptibility. Most cases were severe enough to require veterinary attention and some horses were euthanized. PMID:17423117

  4. [Nocturnal flight activities of Culicoides (Diptera: Ceratopogonidae) species in Konya].

    PubMed

    Dik, Bilal; Ergül, Recep

    2006-01-01

    This study was carried out in order to determine the nocturnal flight activities of Culicoides species during July, 1997 in Konya. Light traps were used for the collection of Culicoides specimens. They were placed in or nearby pens of poultry, sheep and cattle between the hours 20:00-22:00, 22:00-24:00, 24:00-02:00, 02:00-04:00, 04:00-06:00, and 06:00-08:00. A total of 4084 specimens were caught. Twelve species (C. puncticollis, C. maritimus, C. circumscriptus, C. punctatus, C. newsteadi, C. flavipulicaris, C. obsoletus, C. pulicaris, C. simulator, C. gejgelensis, C. salinarius, and C. vexans) were identified. C. puncticollis, C. maritimus, C. circumscriptus and C. punctatus were the most abundant species. It was found that the Culicoides species fly at night and their numbers decrease in the morning. The different species were observed to have different flight activities. A maximum number of C. puncticollis was captured in between the hours 20:00-22:00. A relatively high number of C. maritimus were caught between the hours of 20.00-22.00. Flight activity of this species peaked between the hours 22:00-24:00. The maximum number of C. circumscriptus was captured between the hours of 22:00-24:00 and 24:00-02:00. Flight activity of C. punctatus increased regularly from the hours of 20:00-22:00 until 02:00-04:00. PMID:17160855

  5. COMPARATIVE SALIVARY GLAND TRANSCRIPTOMICS OF THREE GALL MIDGE PESTS OF CEREAL CROPS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many gall midge species are important economic pests of crop plants. Among the most importantare the Hessian fly, Mayetiola destructor, the Asian rice gall midge, Orseolia oryzae, and theorange wheat blossom midge, Sitodiplosis mosellana. The salivary glands of these insects arethe source of the che...

  6. Host plant susceptibility to the swede midge (Diptera: Cecidomyiidae).

    PubMed

    Hallett, Rebecca H

    2007-08-01

    The relative resistance and susceptibility of various cruciferous plants to swede midge, Contarinia nasturtii (Kieffer) (Diptera: Cecidomyiidae), damage was investigated to provide growers with planting recommendations and to identify potential sources of resistance to the swede midge. Broccoli cultivars experienced more severe damage than cabbage, cauliflower, and Brussels sprouts. The broccoli 'Paragon', 'Eureka', and 'Packman' are highly susceptible to the swede midge, whereas 'Triathlon' and 'Regal' showed reduced susceptibility to damage and slower development of damage symptoms. No differences were found between normal and red cultivars of cabbage and cauliflower in damage severity and progression of damage symptoms. Four new plant species (Brassica juncea Integlifolia group, Erucastrum gallicum (Willd.) O. E. Shulz., Lepidium campestre (L.) R.Br., and Capsella bursa-pastoris (L.) Medic.) are reported as hosts of the swede midge. The weed species Descurainia sophia (L.) Webb, Camelina microcarpa Andrz. ex Dc., and Erysimum cheiranthoides L. exhibited no damage symptoms, and they seem to be nonhost crucifers for the swede midge. PMID:17849887

  7. First overview of the Culicoides Latreille (Diptera: Ceratopogonidae) livestock associated species of Reunion Island, Indian Ocean.

    PubMed

    Desvars, A; Grimaud, Y; Guis, H; Esnault, O; Allène, X; Gardès, L; Balenghien, T; Baldet, T; Delécolle, J C; Garros, C

    2015-02-01

    This study establishes the first faunistic inventory of livestock associated Culicoides (Diptera: Ceratopogonidae) species of Reunion Island (Indian Ocean), where bluetongue and epizootic hemorrhagic disease are regularly recorded. Single night-catches were performed at 41 sites using light suction traps at altitudes ranging from 0 to 1525 m, from March to April 2005. Five species were recorded: Culicoides imicola, Culicoides bolitinos, Culicoides enderleini, Culicoides grahamii, and Culicoides kibatiensis, among which at least the first three species are known to be involved in virus transmission to ruminants and equids. This is the first record of C. bolitinos, C. kibatiensis, and C. enderleini on the island. C. imicola was the most abundant species along the sea coast. C. bolitinos was more abundant inland and on two sites on the east coast. C. kibatiensis and C. grahamii were less abundant than the other three species and limited to two foci. Spatial distribution analysis of the different species showed that C. bolitinos, C. enderleini and C. imicola were collected at low altitudes, while the other two species were found at higher altitude. A morphological identification key for adult females and males is given, as well as cytochrome oxydase subunit I sequences. Phylogenetic reconstructions showed a clear divergence between C. bolitinos from Reunion Island and mainland Africa. This monograph will help to identify the Culicoides species in the poorly known entomological fauna of the south-western Indian Ocean region. PMID:25447828

  8. PUTATIVE STRESS REGULATED GENES OF THE ANTARCTIC MIDGE, BELGICA ANTARCTICA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antarctica presents one of the earth’s most inhospitable environments. Though an abundance of animals have adapted to life associated with the sea in this part of the world, few animals have adapted to the rigors of a terrestrial existence. One exception is the flightless midge Belgica antarctica ...

  9. STRESS PROTEINS OF THE ANTARCTIC MIDGE, BELGICA ANTARCTICA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antarctica presents one of the earth’s most inhospitable environments. Though an abundance of animals have adapted to life associated with the sea in this part of the world, few animals have adapted to the rigors of a terrestrial existence. One exception is the flightless midge Belgica antarctica ...

  10. Cues used in host-seeking behavior by frog-biting midges (Corethrella spp. Coquillet).

    PubMed

    Bernal, Ximena E; de Silva, Priyanka

    2015-06-01

    We investigated the role of carbon dioxide and host temperature in host attraction in frog-biting midges (Corethrella spp). In these midges, females are known to use frog calls to localize their host, but the role of other host-emitted cues has yet not been investigated. We hypothesized that carbon dioxide acts as a supplemental cue to frog calls. To test this hypothesis, we determined the responses of the midges to carbon dioxide, frog calls, and both cues. A significantly lower number of midges are attracted to carbon dioxide and silent traps than to traps broadcasting frog calls. Adding carbon dioxide to the calls does not increase the attractiveness to the midges. Instead, carbon dioxide can have deterrent effects on frog-biting midges. Temperature of calling frogs is not a cue potentially available to the midges. Contrary to our hypothesis, there was no supplemental effect of carbon dioxide when presented in conjunction to calls. Midge host-seeking behavior strongly depends on the mating calls emitted by their anuran host. Overall, non-acoustic cues such as host body temperature and carbon dioxide are not important in long-distance host location by frog-biting midges. PMID:26047192

  11. Collective Behaviour without Collective Order in Wild Swarms of Midges

    PubMed Central

    Attanasi, Alessandro; Cavagna, Andrea; Del Castello, Lorenzo; Giardina, Irene; Melillo, Stefania; Parisi, Leonardo; Pohl, Oliver; Rossaro, Bruno; Shen, Edward; Silvestri, Edmondo; Viale, Massimiliano

    2014-01-01

    Collective behaviour is a widespread phenomenon in biology, cutting through a huge span of scales, from cell colonies up to bird flocks and fish schools. The most prominent trait of collective behaviour is the emergence of global order: individuals synchronize their states, giving the stunning impression that the group behaves as one. In many biological systems, though, it is unclear whether global order is present. A paradigmatic case is that of insect swarms, whose erratic movements seem to suggest that group formation is a mere epiphenomenon of the independent interaction of each individual with an external landmark. In these cases, whether or not the group behaves truly collectively is debated. Here, we experimentally study swarms of midges in the field and measure how much the change of direction of one midge affects that of other individuals. We discover that, despite the lack of collective order, swarms display very strong correlations, totally incompatible with models of non-interacting particles. We find that correlation increases sharply with the swarm's density, indicating that the interaction between midges is based on a metric perception mechanism. By means of numerical simulations we demonstrate that such growing correlation is typical of a system close to an ordering transition. Our findings suggest that correlation, rather than order, is the true hallmark of collective behaviour in biological systems. PMID:25057853

  12. Isolation and identification of allelochemicals produced by B. sonorensis for suppression of charcoal rot of Arachis hypogaea L.

    PubMed

    Pandya, Urja; Saraf, Meenu

    2015-05-01

    Bacillus sonorensis MBCU2 isolated from vermicompost-amended soil from Gujarat, India showed most antagonistic activity against Macrophomina phaseolina by dual culture screening. The culture supernatant of MBCU2 completely suppressed the mycelia growth of pathogen, indicating that suppression was due to the presence of allelochemicals in the culture filtrate. Results of scanning electron microscopy revealed that MBCU2 caused morphological alteration in mycelia of M. phaseolina as evident by hyphal lysis and perforation. Lipopeptides (iturin A and surfactin) produced by MBCU2 were detected and identified by MALDI-TOF-MS as well as liquid chromatography coupled with ESI-MS/MS. Pot trial studies conducted by seed bacterization with MBCU2 resulted in statistically significant increase in Arachis hypogaea L. vegetative growth parameters such as root length (91%), shoot length (252%), fresh weight (71%), dry weight (57%), number of pod (128%), and number of seed (290%) in M. phaseolina infested soil over control as well as decreased M. phaseolina disease severity. We suggest that allelochemicals production can be linked to the mechanism of protection of A. hypogaea L. from M. phaseolina by B. sonorensis MBCU2. PMID:25346523

  13. Tripius gyraloura n. sp. (Aphelenchoidea: Sphaerulariidae) parasitic in the gall midge Lasioptera donacis Coutin (Diptera: Cecidomyiidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new nematode, Tripius gyraloura sp. n., is described from the arundo gall midge, Lasioptera donacis Coutin (Diptera: Cecidomyiidae). This gall midge is being considered as a biological control agent for use in North America against the introduced giant reed, Arundo donax (L.) (Poaceae: Cyperales)....

  14. Method refinements for the midge life-cycle, Chironomus dilutus test

    EPA Science Inventory

    Larval stages of non-biting midges can be found in almost any freshwater ecosystem, and one of the commonly tested midges is Chironomus dilutus (Chironomidae, Diptera) which is used for toxicity testing and ecological risk assessment of freshwater contaminants. USEPA, ASTM, Envir...

  15. Seasonal abundance of Culicoides imicola and C. obsoletus in the Balearic islands.

    PubMed

    Miranda, M A; Rincón, C; Borràs, D

    2004-01-01

    An outbreak of bluetongue (BT) was declared on the Balearic islands of Spain in September and October 2000. In 2001 and 2002, an intensive survey was conducted on cattle farms in Majorca and Minorca for the principal vectors in the Mediterranean Basin, Culicoides imicola and C. obsoletus. Adult Culicoides were collected once a week between June 2001 and December 2002 using CDC light traps. The results from 348 light-trap collections revealed that, in addition to other species of the genus Culicoides, both C. imicola and C. obsoletus appear to be well established on both Majorca and Minorca. Furthermore, both species showed a different seasonal abundance pattern: peak adult populations of C. obsoletus occurred in July, while those of C. imicola peaked in October. These findings indicate that the principal vector in the outbreak of BT in the Balearic islands in 2000 was probably C. imicola. PMID:20419681

  16. Studies of the mortality rate of Culicoides imicola in Morocco.

    PubMed

    Baylis, M; Touti, J; Bouayoune, H; Moudni, L; Taoufiq, B; el Hasnaoui, H

    1998-01-01

    Daily mortality rates of female Culicoides imicola were found for eight sites in Morocco in 1994 and for six sites in 1995. The mortality rates were found by operating Pirbright-type light traps for a number of consecutive nights in late summer or autumn and finding the parous rate assuming a feeding interval of 3 to 5 days. The mortality rates were calculated according to established methods. In Morocco the daily mortality rates were found to vary from about 5% per day (Arbaoua, 1994, 1995 and Sidi Moussa 1995) up to 20-25% per day (Berkane, Marrakech, Tangier). In general, estimates of daily mortality rate were consistent between the two years of study. Among sites, daily mortality rate was significantly correlated with the average night-time minimum wind speed but not mean or maximum night-time wind speeds, or with temperature, humidity or saturation deficit. The observed mortality rates suggest that at Arbaoua, were 1,000 flies to become infected with African horse sickness virus, at least 330 would live long enough to take 3 or more infective blood meals on hosts. At Berkane, the survival rate per 1,000 is less than 10. In general, the pattern observed for daily mortality rate, combined with the relative population sizes of C. imicola in Morocco, agree well with the observed distribution of African horse sickness in the country during the 1989-1991 epizootic. PMID:9785502

  17. Characterization of a Hyperthermostable Alkaline Lipase from Bacillus sonorensis 4R.

    PubMed

    Bhosale, Hemlata; Shaheen, Uzma; Kadam, Tukaram

    2016-01-01

    Hyperthermostable alkaline lipase from Bacillus sonorensis 4R was purified and characterized. The enzyme production was carried out at 80°C and 9.0 pH in glucose-tween inorganic salt broth under static conditions for 96 h. Lipase was purified by anion exchange chromatography by 12.15 fold with a yield of 1.98%. The molecular weight of lipase was found to be 21.87 KDa by SDS-PAGE. The enzyme activity was optimal at 80°C with t 1/2 of 150 min and at 90°C, 100°C, 110°C, and 120°C; the respective values were 121.59 min, 90.01 min, 70.01 min, and 50 min. The enzyme was highly activated by Mg and t 1/2 values at 80°C were increased from 150 min to 180 min when magnesium and mannitol were added in combination. The activation energy calculated from Arrhenius plot was 31.102 KJ/mol. At 80-120°C, values of ΔH and ΔG were in the range of 28.16-27.83 KJ/mol and 102.79 KJ/mol to 111.66 KJ/mol, respectively. Lipase activity was highest at 9.0 pH and stable for 2 hours at this pH at 80°C. Pretreatment of lipase with MgSO4 and CaSO4 stimulated enzyme activity by 249.94% and 30.2%, respectively. The enzyme activity was greatly reduced by CoCl2, CdCl2, HgCl2, CuCl2, Pb(NO3)2, PMSF, orlistat, oleic acid, iodine, EDTA, and urea. PMID:26904276

  18. Characterization of a Hyperthermostable Alkaline Lipase from Bacillus sonorensis 4R

    PubMed Central

    Bhosale, Hemlata; Shaheen, Uzma

    2016-01-01

    Hyperthermostable alkaline lipase from Bacillus sonorensis 4R was purified and characterized. The enzyme production was carried out at 80°C and 9.0 pH in glucose-tween inorganic salt broth under static conditions for 96 h. Lipase was purified by anion exchange chromatography by 12.15 fold with a yield of 1.98%. The molecular weight of lipase was found to be 21.87 KDa by SDS-PAGE. The enzyme activity was optimal at 80°C with t1/2 of 150 min and at 90°C, 100°C, 110°C, and 120°C; the respective values were 121.59 min, 90.01 min, 70.01 min, and 50 min. The enzyme was highly activated by Mg and t1/2 values at 80°C were increased from 150 min to 180 min when magnesium and mannitol were added in combination. The activation energy calculated from Arrhenius plot was 31.102 KJ/mol. At 80–120°C, values of ΔH and ΔG were in the range of 28.16–27.83 KJ/mol and 102.79 KJ/mol to 111.66 KJ/mol, respectively. Lipase activity was highest at 9.0 pH and stable for 2 hours at this pH at 80°C. Pretreatment of lipase with MgSO4 and CaSO4 stimulated enzyme activity by 249.94% and 30.2%, respectively. The enzyme activity was greatly reduced by CoCl2, CdCl2, HgCl2, CuCl2, Pb(NO3)2, PMSF, orlistat, oleic acid, iodine, EDTA, and urea. PMID:26904276

  19. Holocene temperature history of northern Iceland inferred from subfossil midges

    NASA Astrophysics Data System (ADS)

    Axford, Yarrow; Miller, Gifford H.; Geirsdóttir, Áslaug; Langdon, Peter G.

    2007-12-01

    The Holocene temperature history of Iceland is not well known, despite Iceland's climatically strategic location at the intersection of major surface currents in the high-latitude North Atlantic. Existing terrestrial records reveal spatially heterogeneous changes in Iceland's glacier extent, vegetation cover, and climate over the Holocene, but these records are temporally discontinuous and mostly qualitative. This paper presents the first quantitative estimates of temperatures throughout the entire Holocene on Iceland. Mean July temperatures are inferred based upon subfossil midge (Chironomidae) assemblages from three coastal lakes in northern Iceland. Midge data from each of the three lakes indicate broadly similar temperature trends, and suggest that the North Icelandic coast experienced relatively cool early Holocene summers and gradual warming throughout the Holocene until after 3 ka. This contrasts with many sites on Iceland and around the high-latitude Northern Hemisphere that experienced an early to mid-Holocene "thermal maximum" in response to enhanced summer insolation forcing. Our results suggest a heightened temperature gradient across Iceland in the early Holocene, with suppressed terrestrial temperatures along the northern coastal fringe, possibly as a result of sea surface conditions on the North Iceland shelf.

  20. Bioprocess development for the production of sonorensin by Bacillus sonorensis MT93 and its application as a food preservative.

    PubMed

    Chopra, Lipsy; Singh, Gurdeep; Jena, Kautilya Kumar; Verma, Himanshu; Sahoo, Debendra K

    2014-10-28

    Media composition and environmental conditions were optimized using statistical tools, Plackett Burman design and response surface methodology, to maximize the yield of a bacteriocin, named as sonorensin, from a new marine isolate Bacillus sonorensis MT93 showing broad spectrum of antimicrobial activity. Under optimized conditions, MT93 produced 15-fold higher yield of sonorensin compared to that under initial fermentation conditions. As oxygen supply is a critical parameter controlling growth and product formation in aerobic bioprocesses and used as a parameter for bioprocess scale up, the effects of oxygen transfer, in terms of volumetric oxygen transfer coefficient (kLa), on production of sonorensin was investigated using optimized medium composition in a bioreactor. Studies on effectiveness of sonorensin against Staphylococcus aureus and Listeria monocytogenes in fruit juice and as a preservative in pasteurized milk demonstrated its potential as a biopreservative in fruit products and shelf life extender of the pasteurized milk. PMID:25459843

  1. Redescription of Campoletis sonorensis (Cameron, 1886) (Hymenoptera, Ichneumonidae, Campopleginae), parasitoid of Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera, Noctuidae) in Brazil.

    PubMed

    Camargo, L F; Brito, R A; Penteado-Dias, A M

    2015-11-01

    The fall armyworm Spodoptera frugiperda (Lepidoptera; Noctuidae) is a voracious pest of numerous crops of economic importance throughout the New World. In Brazil, its larvae are attacked by several species of parasitoid wasps, making them potential candidate as biological control agents against this pest. A survey of the parasitoid fauna on S. frugiperda in maize crops throughout Brazil reveals two species of Campoletis, which are morphologicaly very similar species. In this paper we combine these data with pictures from the type material of C. sonorensis and C. flavicincta, as well as their descriptions to provide a redescription to Campoletis sonorensis (Cameron, 1886) using for this both morphological characters and DNA Barcoding (Hebert et al., 2003) information, in an attempt to help with the correct identification of the taxa to improve biological control studies. PMID:26675917

  2. Sonorensin: an Antimicrobial Peptide, Belonging to the Heterocycloanthracin Subfamily of Bacteriocins, from a New Marine Isolate, Bacillus sonorensis MT93

    PubMed Central

    Chopra, Lipsy; Singh, Gurdeep; Choudhary, Vikas

    2014-01-01

    Marine environments are the greatest fronts of biodiversity, representing a resource of unexploited or unknown microorganisms and new substances having potential applications. Among microbial products, antimicrobial peptides (AMPs) have received great attention recently due to their applications as food preservatives and therapeutic agents. A new marine soil isolate producing an AMP was identified as Bacillus sonorensis based on 16S rRNA gene sequence analysis. It produced an AMP that showed a broad spectrum of activity against both Gram-positive and Gram-negative bacteria. The peptide, named sonorensin, was purified to homogeneity using a combination of chromatographic techniques. The intact molecular mass of the purified peptide, 6,274 Da, as revealed by matrix-assisted laser desorption ionization–time of flight (MALDI-TOF), was in agreement with Tricine-SDS-PAGE analysis. A PCR array of primers was used to identify AMP structural genes, which allowed the successful amplification of the related genes from strain MT93. The putative open reading frame of sonorensin was amplified, cloned into the pET-32a(+) vector, expressed as a thioredoxin (Trx) fusion protein in Escherichia coli, and then purified. Sequence alignment analysis revealed that the bacteriocin being reported could belong to new subfamily of bacteriocins, heterocycloanthracin. The peptide indicated its potential as a biocontrol agent or food antimicrobial agent, due to its antimicrobial activity against bacteria such as Listeria monocytogenes and Staphylococcus aureus. This is the first report of the production, purification, and characterization of wild-type and recombinant bacteriocin by B. sonorensis and the first bacteriocin of the heterocycloanthracin subfamily to be characterized. PMID:24610839

  3. CHRONIC EFFECTS OF THE HERBICIDE DIURON ON FRESHWATER CLADOCERANS,AMPHIPODS,MIDGES,MINNOWS,WORMS, AND SNAILS

    EPA Science Inventory

    The chronic effects of the herbicide diuron on survival and reproduction of Daphnia pulex, and survival and growth of the amphipod Hyalella azteca, the midge Chironomus tentans, juvenile and embro/larval fathead minnows, Pimephales promelas, annelid worms, Lumbriculus variegatus,...

  4. Chironomid midges (Diptera, chironomidae) show extremely small genome sizes.

    PubMed

    Cornette, Richard; Gusev, Oleg; Nakahara, Yuichi; Shimura, Sachiko; Kikawada, Takahiro; Okuda, Takashi

    2015-06-01

    Chironomid midges (Diptera; Chironomidae) are found in various environments from the high Arctic to the Antarctic, including temperate and tropical regions. In many freshwater habitats, members of this family are among the most abundant invertebrates. In the present study, the genome sizes of 25 chironomid species were determined by flow cytometry and the resulting C-values ranged from 0.07 to 0.20 pg DNA (i.e. from about 68 to 195 Mbp). These genome sizes were uniformly very small and included, to our knowledge, the smallest genome sizes recorded to date among insects. Small proportion of transposable elements and short intron sizes were suggested to contribute to the reduction of genome sizes in chironomids. We discuss about the possible developmental and physiological advantages of having a small genome size and about putative implications for the ecological success of the family Chironomidae. PMID:26003979

  5. Is the morphology of Culicoides intersexes parasitized by mermithid nematodes a parasite adaptation? A morphometric approach to Culicoides circumscriptus (Diptera: Ceratopogonidae).

    PubMed

    Muñoz-Muñoz, Francesc; Ramoneda, Josep; Pagès, Nonito; Pujol, Nuria; Talavera, Sandra

    2016-03-01

    Mermithidae is a family of endoparasitic nematodes known to cause intersexuality in arthropods. Intersexes of the genus Culicoides parasitized by mermithids have been the object of several studies aiming to describe their particular morphology. Culicoides intersexes are specimens with male genitalia and feminized sexually dimorphic structures, i.e. antennae, mouthparts and wings. To date, these specimens have only been described qualitatively and a quantitative approach supported by statistical analysis is lacking. Here we conduct morphometric analyses of sexually dimorphic structures in a sample of Culicoides circumscriptus that includes 34 intersexes with the aim of describing precisely the intersexual morphology. The morphology of antennae and the mouthparts was studied by multivariate statistical analysis of linear measures, and wing form by implementing geometric morphometrics techniques. While intersex wings proved to have a similar size to male wings, their shape was intermediate between males and females. However, when allometric shape variation was removed, the wing shape of intersexes was almost identical to that of females. The intersex antennae were morphometrically of the female type, especially when size variation was considered. In contrast, the measured mouthparts (the labrum and the third palpal segment) were halfway between males and females, even when body size was considered. Overall, the antennae and the wings showed a higher degree of feminization than the mouthparts. These findings indicate that the degree of feminization depends both on the morphological structure and on body size. Moreover, we propose that the feminization of the wings and antennae has an adaptive meaning for the parasite, which would favor female-like traits in order to access more easily its breeding sites, where the parasite has plenty of new hosts to infect. Female-like antennae would be beneficial to detect these sites, while having female-like wings would favor the

  6. Isolation of haemolytic bacilli from field-collected Culicoides oxystoma and Culicoides peregrinus: potential vectors of bluetongue virus in West Bengal, India.

    PubMed

    Harsha, R; Pan, B; Ghosh, K; Mazumdar, A

    2015-06-01

    Two haemolytic bacterial strains of Bacillus pumilus (CU1A, CU1B) and one blood-utilizing strain of Bacillus licheniformis (CU2B) were isolated from relatively low numbers of field-collected females of Culicoides oxystoma and Culicoides peregrinus (Diptera: Ceratopogonidae). A total of 36 females, including 18 of each of C. oxystoma and C. peregrinus (consisting of one and a pool of eight blood-engorged specimens, and one and a pool of eight non-engorged specimens for each species), were tested. In C. oxystoma, all three strains of bacteria were isolated from the one non-engorged, the pool of non-engorged and the pool of blood-engorged females tested, but CU1A and CU2B were not found in the one blood-engorged female tested. In C. peregrinus, all three strains were present in the pool of blood-engorged females. However, the strain CU2B was not found in the pool of non-engorged females. In the one blood-engorged and one non-engorged female tested, CU1A and CU2B were detected. The bacterial strains were identified based on Gram staining, enzyme activity (amylase and protease) and alignment of the 16S rRNA partial gene sequence to that available in the National Center for Biotechnology Information (NCBI) database GenBank. The functional role and significance of these haemolytic and blood-digesting bacteria within the genus Culicoides remain to be determined. PMID:25644315

  7. Modelling spatio-temporal patterns of long-distance Culicoides dispersal into northern Australia.

    PubMed

    Eagles, D; Walker, P J; Zalucki, M P; Durr, P A

    2013-07-01

    Novel arboviruses, including new serotypes of bluetongue virus, are isolated intermittently from cattle and insects in northern Australia. These viruses are thought to be introduced via windborne dispersal of Culicoides from neighbouring land masses to the north. We used the HYSPLIT particle dispersal model to simulate the spatio-temporal patterns of Culicoides dispersal into northern Australia from nine putative source sites across Indonesia, Timor-Leste and Papua New Guinea. Simulated dispersal was found to be possible from each site, with the islands of Timor and Sumba highlighted as the likely principal sources and February the predominant month of dispersal. The results of this study define the likely spatial extent of the source and arrival regions, the relative frequency of dispersal from the putative sources and the temporal nature of seasonal winds from source sites into arrival regions. Importantly, the methodology and results may be applicable to other insect and pathogen incursions into northern Australia. PMID:23642857

  8. Culicoides hypersensitivity in the horse: 15 cases in southwestern british columbia.

    PubMed

    Kleider, N; Lees, M J

    1984-01-01

    The investigation of a chronic, seasonal dermatitis of horses in southwestern British Columbia is described. Typically the history indicated an insidious onset, followed by a gradual progression in the severity of the signs each year. Lesions appeared during the warmer months of the year and tended to regress during the winter. The clinical signs consisted of areas of pruritus and excoriation, affecting predominantly the ventral midline, mane and tailhead. In all cases corticosteroid therapy relieved the pruritus and allowed the lesions to heal.The salient pathological findings were hyperkeratosis, spongiosis and a dermal infiltration of eosinophils together with mononuclear cells. These changes are typical of an allergic dermatitis, which has been recognized in many parts of the world as a hypersensitivity reaction to the bites of Culicoides spp. In this instance, the epidemiological findings relating to the geographic area, the local insect population and the distribution of lesions implicated Culicoides obsoletus as the etiological agent. PMID:17422351

  9. Identification of Culicoides obsoletus (Diptera: Ceratopogonidae) as a vector of bluetongue virus in central Italy.

    PubMed

    De Liberato, C; Scavia, G; Lorenzetti, R; Scaramozzino, P; Amaddeo, D; Cardeti, G; Scicluna, M; Ferrari, G; Autorino, G L

    2005-03-01

    In 2001 and 2002, 235 outbreaks of bluetongue were observed in the Lazio and Tuscany regions of central Italy. During entomological surveillance Culicoides imicola, the main vector of bluetongue virus in the Mediterranean region, was detected in only 14 of 28 municipalities affected by outbreaks; Culicoides obsoletus was the most abundant species, contributing 83 per cent of individuals in catches, whereas C. imicola contributed only 2 per cent. In affected municipalities the maximum catch of C. obsoletus was 18,000 specimens, compared with 54 of C. imicola. In October 2002 bluetongue virus serotype 2 was isolated from a single pool of wild-caught, non-blood-engorged parous C. obsoletus inoculated on to BHK-21 cells. Its identity was confirmed by reverse transcriptase-PCR. PMID:15786918

  10. Improving light-trap efficiency for Culicoides spp. with light-emitting diodes.

    PubMed

    Bishop, A L; Worrall, R J; Spohr, L J; McKenzie, H J; Barchia, I M

    2004-01-01

    The robustness of light traps used to monitor Culicoides spp. throughout Australia was improved with stainless steel and heavy duty plastic fittings. Printed circuit boards and light-dependent resistors were modified to be compatible with recent advances in electronics. In experiments with light-emitting diodes (LEDs), C. brevitarsis Kieffer was significantly attracted to green light. This species is the major vector of Akabane and bluetongue viruses in Australia and is the main target of a national monitoring programme using light traps. This response was significantly greater than the response to the incandescent lights currently used in the light traps. Catches of C. brevitarsis were also related to the intensity of the green LEDs. These were more effective than the currently used incandescent globes at intensities between 46% and 142% of the incandescent intensity. The response of seven other Culicoides spp. to the LEDs was also determined. PMID:20419675

  11. The effect of climate on the presence of Culicoides imicola in Italy.

    PubMed

    Conte, A; Giovannini, A; Savini, L; Goffredo, M; Calistri, P; Meiswinkel, R

    2003-04-01

    A model was developed to classify the Italian territories in relation to their suitability to harbour populations of Culicoides imicola and, as a consequence, also able to sustain a bluetongue (BT) epidemic. Italy was subdivided into 3507 10 x 10 km cells. In 546 cells at least one collection was made. The cell was considered the unit for all subsequent analyses. Culicoides were collected using Onderstepoort-type blacklight traps. Some traps were operated weekly at chosen sites; the remainder were moved almost daily to new sites. Only the results obtained during the peak August-November period were used, to exclude bias caused by the seasonality of C. imicola. Climate data for the period 1999-2001 were obtained from 80 weather stations. Multiple logistic regression was performed using the presence or absence of C. imicola in a specific cell as the dependent variable. Annual means of daily values for minimum temperature and minimum relative humidity, and the mean altitude above sea level, were the independent variables. The probability of occurrence of C. imicola in each grid cell was used to create a prediction map for Italy. The model was able to correctly classify 77.5% of the 546 grid cells in which at least one collection had been made. Culicoides imicola was found frequently through much of Sardinia, in parts of southern Italy, and further north along the Tyrrhenian coast, but was absent from along most of the Adriatic coast, and the internal mainland, and from most of Sicily. Six detailed maps are provided. Also mapped are areas where the probability of the occurrence of C. imicola is lower than 5%. This identification of possible mountainous C. imicola-free areas in central Italy could facilitate safer animal trade and transhumance, even if BT infections in traded animals or moving stock, were to go undetected. Needless to say this depends upon no cool-adapted species of Culicoides being involved in the transmission of BT disease. PMID:12667192

  12. Evaluation of a eucalyptus-based repellent against Culicoides impunctatus (Diptera:Ceratopogonidae) in Scotland.

    PubMed

    Trigg, J K

    1996-06-01

    A eucalyptus-based insect repellent (PMD) was evaluated against Culicoides impunctatus in Scotland in comparison with deet. In human landing catches, both repellents still afforded 98% protection from biting 8 h after application of 0.5 ml to the forearm. A second trial looking at protection between 8 and 10 h after repellent application showed 99.5% protection for PMD and 97% for deet as compared with controls. PMID:8827615

  13. [Ceratopogonidae (Diptera) of the Congolese Mayombe. II. Contribution to the study of a Culicoides community].

    PubMed

    Itoua, A; Vattier-Bernard, G; Trouillet, J

    1987-01-01

    Owing to adapted methods of sampling and regular captures carried out during one year, the study of a Culicoides community could be realized in the Mayombe mountain in Congo. Nineteen species were recorded. Quantity and frequency of each of them have been computed. For the principal species feeding habits, phototaxis, sex-ratio, seasonal fluctuations are analysed. Influence of climatic parameters is discussed. PMID:3426078

  14. Isolation of Tibet orbivirus, TIBOV, from Culicoides Collected in Yunnan, China

    PubMed Central

    Feng, Yun; Nie, Kai; Song, Jingdong; Li, Yang; Ma, Xuejun; Liang, Guodong; Zhou, Hongning

    2015-01-01

    We isolated a novel virus strain (YN12246) from Culicoides spp. specimens collected at the China-Laos-Myanmar border in southern Yunnan Province. This virus had a cytopathic effect (CPE) on both insect cells (C6/36) and mammalian cells (BHK-21). Electron microscopy revealed the structure of the virions to be spherical with a diameter of 75 nm. Polyacrylamide gel analysis demonstrated that the viral genome consisted of 10 segments of double-stranded RNA (dsRNA), with a distribution pattern of 3-3-3-1. The coding sequences of 9 genome segments of YN12246 (Seg1, Seg3-Seg10) were obtained by high-throughput sequencing and Sanger sequencing. Comparisons of conserved genome segments 1 and 3 (Seg1 and Seg3), encoding the polymerase-VP1 and sub-core T2 protein, respectively, showed that YN12246 groups with the Culicoides-borne orbiviruses. The highest levels of sequence identity were detected between YN12246 and Tibet orbivirus (TIBOV), indicating that they belong to the same virus species (with amino acid identity of 98.8% and 96.4% for the polymerase and T2 protein, respectively). The data presented here confirm that YN12246 is a member of the TIBOV species, which was first isolated from mosquitoes in 2009. This is the first report of the isolation of TIBOV from Culicoides. PMID:26295700

  15. Responses of the aquatic midge Chironomus riparius to DEET exposure.

    PubMed

    Campos, Diana; Gravato, Carlos; Quintaneiro, Carla; Soares, Amadeu M V M; Pestana, João L T

    2016-03-01

    N,N-diethyl-3-methylbenzamide (DEET) is the active ingredient of many commercial insect repellents. Despite being detected worldwide in effluents, surface water and groundwater, there is still limited information on DEET's toxicity toward non-target aquatic invertebrates. Thus, our main objective was to assess the effects of DEET in the life cycle of Chironomus riparius and assess its biochemical effects. Laboratory assays showed that DEET reduced developmental rates (reduced larval growth, delayed emergence) of C. riparius larvae and also caused a decrease in the size of adult midges. Concerning the biochemical responses, a short exposure to DEET caused no effects in lipid peroxidation, despite the significant inhibition of catalase and glutathione-S-transferase activities and of total glutathione contents. Moreover, inhibition of acetylcholinesterase activity was also observed showing neurotoxic effects. Environmental risk assessment of insect repellents is needed. Our results showed moderate toxicity of DEET toward C. riparius, however, due to their mode of action, indirect ecological effects of DEET and of other insect repellents cannot be excluded and should be evaluated. PMID:26773354

  16. Midges as palaeoindicators of lake productivity, eutrophication and hypolimnetic oxygen

    NASA Astrophysics Data System (ADS)

    Brodersen, Klaus Peter; Quinlan, Roberto

    2006-08-01

    The sedimentary record from lakes can be used as an archive of past environmental changes and for events related to anthropogenic activities in the catchment area. In this paper, we review the more recent studies on zoobenthos responses to changes in lake productivity and to altered sublittoral and hypolimnetic oxygen conditions, as reflected from subfossil midge (Diptera: Chironomidae) assemblages and palaeostratigraphies. We discuss how the importance of different environmental variables is scale dependent in both time and space and we summarize some of the classical and general patterns in chironomid palaeolimnology. The recent advances in quantitative reconstructions using chironomid transfer functions and numerical analyses are presented and compared. A consensus ranking of species trophic optima and respiratory adaptations from published data sets showed good agreement. Factors such as lake depth, stratification patterns, water level change, sediment conditions, submerged vegetation and ecological thresholds are all important for interpretation of palaeolimnological trajectories. We use previously published and new data to document how these factors determine, change or preserve the "lake identity" over time. We conclude that subfossil chironomids have proven to be very effective indicators for lake trophic development (productivity) and hypolimnetic oxygen conditions. Challenges in interpreting the subfossil chironomid record include the interaction between a range of scale-dependent variables and processes.

  17. Modelling the Abundances of Two Major Culicoides (Diptera: Ceratopogonidae) Species in the Niayes Area of Senegal.

    PubMed

    Diarra, Maryam; Fall, Moussa; Lancelot, Renaud; Diop, Aliou; Fall, Assane G; Dicko, Ahmadou; Seck, Momar Talla; Garros, Claire; Allène, Xavier; Rakotoarivony, Ignace; Bakhoum, Mame Thierno; Bouyer, Jérémy; Guis, Hélène

    2015-01-01

    In Senegal, considerable mortality in the equine population and hence major economic losses were caused by the African horse sickness (AHS) epizootic in 2007. Culicoides oxystoma and Culicoides imicola, known or suspected of being vectors of bluetongue and AHS viruses are two predominant species in the vicinity of horses and are present all year-round in Niayes area, Senegal. The aim of this study was to better understand the environmental and climatic drivers of the dynamics of these two species. Culicoides collections were obtained using OVI (Onderstepoort Veterinary Institute) light traps at each of the 5 sites for three nights of consecutive collection per month over one year. Cross Correlation Map analysis was performed to determine the time-lags for which environmental variables and abundance data were the most correlated. C. oxystoma and C. imicola count data were highly variable and overdispersed. Despite modelling large Culicoides counts (over 220,000 Culicoides captured in 354 night-traps), using on-site climate measures, overdispersion persisted in Poisson, negative binomial, Poisson regression mixed-effect with random effect at the site of capture models. The only model able to take into account overdispersion was the Poisson regression mixed-effect model with nested random effects at the site and date of capture levels. According to this model, meteorological variables that contribute to explaining the dynamics of C. oxystoma and C. imicola abundances were: mean temperature and relative humidity of the capture day, mean humidity between 21 and 19 days prior a capture event, density of ruminants, percentage cover of water bodies within a 2 km radius and interaction between temperature and humidity for C. oxystoma; mean rainfall and NDVI of the capture day and percentage cover of water bodies for C. imicola. Other variables such as soil moisture, wind speed, degree days, land cover or landscape metrics could be tested to improve the models. Further work

  18. A chironomid (Diptera: Chironomidae) midge population study and laboratory evaluation of larvicides against midges inhabiting the lagoon of Venice, Italy.

    PubMed

    Ali, A; Majori, G; Ceretti, G; D'Andrea, F; Scattolin, M; Ferrarese, U

    1985-03-01

    Chironomid larval densities in the saltwater lagoon of Venice, Italy, were assessed in the spring of 1984. Four organophosphates; chlorpyrifos, temephos, fenthion and fenitrothion, and three pyrethroids; cypermethrin, permethrin and deltamethrin, were tested in the laboratory against field-collected larvae. Three industrial formulations of Bacillus thuringiensis var. israelensis (B.t.i.) were also tested as midge larvicides. Only Chironomus salinarius occurred in the benthic samples taken from different sections of the lagoon. The densities of this species ranged from 0 to 38,976 larvae/m2. The highest mean larval density of 15,673/m2 was encountered in a section of the lagoon adjacent to Venice airport and receiving large quantities of raw sewage. The lowest mean density (less than 1 larva/m2) existed in another area of the lagoon receiving discharge from chemical industry. Cypermethrin and permethrin were 21-233X more active against the larvae than the four organophosphates. Chlorpyrifos was the most active organophosphate. Formulations of B.t.i. were economically ineffective against the larvae. PMID:3880214

  19. Complete mitochondrial genome of the Antarctic midge Parochlus steinenii (Diptera: Chironomidae).

    PubMed

    Kim, Sanghee; Kim, Hanna; Shin, Seung Chul

    2016-09-01

    Parochlus steinenii is a winged midge found in the Antarctic Peninsula and its offshore islands. We determined the complete mitochondrial genome sequence of P. steinenii, which is comprised of 16 803 nucleotides and contains 13 protein-coding genes (PCGs), 22 tRNA genes, and the large (rrnL) and small (rrnS) rRNA genes. Its total A + T content is 72.5%. The PCG arrangement of P. steinenii is identical to that of the ancestral Diptera ground pattern. This is the first report on the mitogenome sequence of an Antarctic midge, and provides insights into the evolution of dipterans in Antarctica. PMID:26642812

  20. Increased interleukin-1beta mRNA expression in skin biopsies of horses with Culicoides hypersensitivity following challenge with Culicoides nubeculosus extract.

    PubMed

    Kolm, Gabriela; Knapp, Elzbieta; Wagner, Regina; Klein, Dieter

    2006-09-15

    Interleukin-1beta (IL-1beta) is a primary cytokine of the skin that has a pivotal role in keratinocyte differentiation, epidermal wound healing and host defense. Pathological increase of cutaneous IL-1beta is associated with edema formation, epidermal hyperproliferation and atopic dermatitis in humans. However, in horses the role of cutaneous IL-1beta in edema formation and allergic skin disease has not been characterised so far. Particularly in Culicoides hypersensitivity (CHS), intradermal injection of Culicoides extract may be associated with enhanced transcription of local IL-1beta. To examine the mRNA expression of IL-1beta and its receptor antagonist IL-1RA in the skin of horses, biopsy specimens of horses affected and non-affected by CHS prior and following intradermal challenge with a commercial C. nubeculosus extract were examined. Our hypothesis was that cutaneous IL-1beta mRNA was significantly upregulated in horses with CHS in response to Culicoides allergen. Biopsies were taken from sites prior to and 4 h following intradermal challenge with C. nubeculosus extract. In order to obtain reliable data, real time PCR was performed and genes of interest were normalized using three different housekeeping genes, beta-actin, GAPDH, beta-2-microglobulin. No significant difference was detected in non-challenged cutaneous IL-1beta mRNA and IL-1RA mRNA levels between CHS affected and non-affected horses. Intradermal injection of C. nubeculosus extract resulted in local upregulation of IL-1beta mRNA both in horses with typical history, characteristic clinical signs for CHS and a positive intradermal skin test (IDT), and non-affected horses with a negative IDT. However, the difference in prior and post challenged site IL-1beta mRNA levels only reached statistical significance in the affected horses (p=0.01 versus 0.7). In contrast, IL-1RA mRNA levels did not demonstrate any modification following intradermal injection with C. nubeculosus in either group. In contrast

  1. Population genetic structure of two primary parasitoids of Spodoptera frugiperda (Lepidoptera), Chelonus insularis and Campoletis sonorensis (Hymenoptera): to what extent is the host plant important?

    PubMed

    Jourdie, Violaine; Alvarez, Nadir; Molina-Ochoa, Jaime; Williams, Trevor; Bergvinson, David; Benrey, Betty; Turlings, Ted C J; Franck, Pierre

    2010-05-01

    Plant chemistry can strongly influence interactions between herbivores and their natural enemies, either by providing volatile compounds that serve as foraging cues for parasitoids or predators, or by affecting the quality of herbivores as hosts or prey. Through these effects plants may influence parasitoid population genetic structure. We tested for a possible specialization on specific crop plants in Chelonus insularis and Campoletis sonorensis, two primary parasitoids of the fall armyworm, Spodoptera frugiperda. Throughout Mexico, S. frugiperda larvae were collected from their main host plants, maize and sorghum and parasitoids that emerged from the larvae were used for subsequent comparison by molecular analysis. Genetic variation at eight and 11 microsatellites were respectively assayed for C. insularis and C. sonorensis to examine isolation by distance, host plant and regional effects. Kinship analyses were also performed to assess female migration among host-plants. The analyses showed considerable within population variation and revealed a significant regional effect. No effect of host plant on population structure of either of the two parasitoid species was found. Isolation by distance was observed at the individual level, but not at the population level. Kinship analyses revealed significantly more genetically related--or kin--individuals on the same plant species than on different plant species, suggesting that locally, mothers preferentially stay on the same plant species. Although the standard population genetics parameters showed no effect of plant species on population structure, the kinship analyses revealed that mothers exhibit plant species fidelity, which may speed up divergence if adaptation were to occur. PMID:20406384

  2. Comparison of Vertebrate Cytochrome b and Prepronociceptin for Blood Meal Analyses in Culicoides

    PubMed Central

    Hadj-Henni, Leila; De Meulemeester, Thibaut; Depaquit, Jérôme; Noël, Philippe; Germain, Adeline; Helder, Remi; Augot, Denis

    2015-01-01

    To date, studies on host preferences and blood meal identification have been conducted for Culicoides species using molecular-based methods such as PCR techniques to amplify only a fragment from universal vertebrate mitochondrial genes such as cytochrome c oxidase subunit I or cytochrome b (Cyt b). The vertebrate prepronociceptin gene (PNOC) was also tested in this field. However, the choice of molecular marker to identify blood meal is critical. The objective of our study is to compare the ability of Cyt b and PNOC as molecular markers for blood meal identification depending on the stage of blood meal digestion. In order to determine whether these Cyt b and PNOC could provide a positive result, 565 blood-fed females of Culicoides spp were collected and morphologically identified. The samples were collected between 2012 and 2014, in two localities in France. The collection localities were near either livestock or a forest. To catch the specimens, we used UV CDC miniature light traps. PNOC sequence of donkeys (Equus asinus) was sequenced and submitted because it was missing in GenBank. Our findings emphasize that the PNOC marker is not suitable to separate closely related Equid species such as horses and donkeys. The Cyt b marker was able to identify 204 more samples when compared to PNOC (99.55% of specimens). Cyt b appears to be better able to detect the origin of blood meals from females with digested blood in their abdomens. We conclude that Cyt b is a good marker as it increases the accuracy of blood meal identification of engorged females containing digested blood in their abdomens. The host opportunist behavior of Culicoides, especially that of C. obsoletus and C. scoticus, the main vectors of BTV in Europe was also highlighted. PMID:26664944

  3. The North American gall midges (Diptera: Cecidomyiidae) of hackberries (Cannabaceae: Celtis spp.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twenty-three species of gall midges occur exclusively on hackberries in North America north of Mexico. Twenty-one of them belong to Celticecis and form complex, dehiscent galls on leaves and the current year’s twigs. Celticecis are definitely known only from the typical subgenus of Celtis that is di...

  4. Community Structure of Chironomidae (Midges) in Two Brazilian Rivers in Relation to Contrasting Land Uses

    NASA Astrophysics Data System (ADS)

    Sonoda, K. C.; Matthaei, C.; Vettorazzi, C. A.; Trivinho-Strixino, S.

    2005-05-01

    We investigated whether the conversion of riparian land use from indigenous forest to pasture is associated with changes in midge community composition in two South Brasilian rivers. Our study was conducted in the main rivers (Sao Jose dos Dourados 6th order; Aguapei 7th order) of two catchments in Sao Paulo State. Both catchments are dominated by agricultural ecosystems but retain substantial patches of native riparian forest in certain areas. Replicated artificial substrates (baskets filled with clay rocks) were exposed in forested and pasture reaches in both rivers. Both land uses had to be present for at least 500m along both river banks, and the riparian forest had to be at least 50m wide. In each river, six baskets per reach type were sampled after a colonization period of 44 days, and all Chironomidae in these samples were sorted and identified to genus level (a total of 3399 individuals belonging to 28 different taxa). As expected, land use affected midge communities. Total midge density was significantly higher in pasture reaches than in forested reaches. By contrast, midge taxon richness was higher at the forested reaches. These results show the importance of native riparian forests for preserving aquatic biodiversity in Brasilian rivers.

  5. Blueberry gall midge: A major insect pest of blueberries in the southeastern United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blueberry gall midge (BGM) (Dasineura oxycoccana: Ceccidomyidae) is a major pest of blueberries in the southeast United States. Larvae attack leaf and flower buds, causing up to 80% yield loss. Eggs hatch in a few days and larvae develop inside the protective bud. Larval feeding destroys the bud ...

  6. Massive shift in gene expression during transitions between developmental stages of the Gall Midge, Mayetiola destructor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The gall midge Mayetiola destructor is a destructive pest of wheat worldwide and a model organism for studying plant – insect interactions. The insect has six different developmental stages including eggs, three instars of larvae, pupae, and adults. Molecular mechanisms controlling the transition ...

  7. Dehydration, rehydration and overhydration alter patterns of gene expression in the Antarctic midge, Belgica antarctica

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We investigated molecular responses elicited by three types of dehydration (fast, slow and cryoprotective), rehydration and overhydration in larvae of the Antarctic midge, Belgica antarctica. The larvae spend most the year encased in ice but during the austral summer are vulnerable to summer storms,...

  8. Gene characterization of two digestive serine proteases in orange blossom wheat midge (Sitodiplosis mosellana)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two full length cDNA sequences, encoding digestive serine proteases (designated as SmPROT-1 and SmPROT-2), were recovered from the midgut of the wheat midge, Sitodiplosis mosellana in an ongoing EST project. The deduced amino acid sequences shared homology with digestive serine proteases from insect...

  9. Cryoprotective dehydration and the resistance to inoculative freezing in the Antarctic midge, Belgica antarctica

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During winter, larvae of the Antarctic midge, Belgica antarctica (Diptera, Chironomidae), must endure 7–8 months of continuous subzero temperatures, encasement in a matrix of soil and ice, and severely desiccating conditions. This environment, along with the fact that larvae possess a high rate of w...

  10. UPREGULATION OF STRESS ASSOCIATED GENES IN THE OVERWINTERING STAGES OF THE ANTARCTIC MIDGE, BELGICA ANTARCTICA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have investigated the molecular basis of stress resistance in the midge Belgica antarctica, the largest known free-living animal to adapt to a terrestrial existence on the Antarctic continent. Prevalent in specific locations throughout the Antarctic peninsula, this insect has a two-year life cyc...

  11. Dewatering as a non-toxic control of nuisance midge larvae in algal wastewater treatment floways.

    PubMed

    Keller, Troy A; Husted, Emily M

    2015-01-01

    Attached-algae floways have tremendous potential for use in wastewater treatment because natural algal communities show high nutrient removal efficiencies, have low operating costs, and are easy to maintain. Algal wastewater floways may also serve as a sustainable option for producing renewable energy because algae grow rapidly, are easily harvested, and can serve as a source of biomass for biofuel. However, pests such as chironomids (Diptera) colonize open channel periphyton floways and their larvae damage the biofilms. While pesticides can control midge larvae, little information is known about alternative, non-toxic controls. This study examined the effectiveness of periodic, short-term dewatering (4 hours every 9 days) on midge abundance and periphyton growth in 16 recirculating, outdoor floways (3 m long, 0.1 m wide). We compared midge abundance and algal accumulation (chlorophyll a, b, c, and pheophytin) among control (n=8) and dewatered (n=8) floways filled with secondarily treated wastewater (27 days, 10 hours of daylight). Dewatered flumes had 42% fewer midges and 28-49% lower algal productivity (as measured by chlorophyll a, b, c, and pheophytin pigments). Chlorophyll a production rates averaged (±1 SD) 0.5±0.2 μg/cm2/day in control floways compared to 0.3±0.1 μg/cm2/day dewatered floways. Short-term dewatering effectively reduced midges but also damaged periphyton. To maximize the recovery of periphyton biomass, operators should harvest periphyton from floways during dewatering events before periphyton is damaged by desiccation or direct exposure to sunlight. PMID:25607663

  12. Analysis of SSH library of rice variety Aganni reveals candidate gall midge resistance genes.

    PubMed

    Divya, Dhanasekar; Singh, Y Tunginba; Nair, Suresh; Bentur, J S

    2016-03-01

    The Asian rice gall midge, Orseolia oryzae, is a serious insect pest causing extensive yield loss. Interaction between the gall midge and rice genotypes is known to be on a gene-for-gene basis. Here, we report molecular basis of HR- (hypersensitive reaction-negative) type of resistance in Aganni (an indica rice variety possessing gall midge resistance gene Gm8) through the construction and analysis of a suppressive subtraction hybridization (SSH) cDNA library. In all, 2,800 positive clones were sequenced and analyzed. The high-quality ESTs were assembled into 448 non-redundant gene sequences. Homology search with the NCBI databases, using BlastX and BlastN, revealed that 73% of the clones showed homology to genes with known function and majority of ESTs belonged to the gene ontology category 'biological process'. Validation of 27 putative candidate gall midge resistance genes through real-time PCR, following gall midge infestation, in contrasting parents and their derived pre-NILs (near isogenic lines) revealed induction of specific genes related to defense and metabolism. Interestingly, four genes, belonging to families of leucine-rich repeat (LRR), heat shock protein (HSP), pathogenesis related protein (PR), and NAC domain-containing protein, implicated in conferring HR+ type of resistance, were found to be up-regulated in Aganni. Two of the reactive oxygen intermediates (ROI)-scavenging-enzyme-coding genes Cytosolic Ascorbate Peroxidase1, 2 (OsAPx1 and OsAPx2) were found up-regulated in Aganni in incompatible interaction possibly suppressing HR. We suggest that Aganni has a deviant form of inducible, salicylic acid (SA)-mediated resistance but without HR. PMID:26801786

  13. [Studies on the massive flights of chironomid midges (Diptera: Chironomidae) as nuisance insects and plans for their control in the Lake Suwa area, central Japan. 2. Quantitative evaluations of the nuisance of chironomid midges].

    PubMed

    Hirabayashi, K

    1991-06-01

    In order to make clear the present "nuisance" caused by chironomid midges around a eutrophic lake, a questionnaire survey of 249 leaders of the Hygiene Self-governing Association of the cities of Suwa and Okaya and the town of Shimosuwa near Lake Suwa was conducted. The results are as follows: 1. More than 90% of the respondents had specific knowledge about the chironomid midge, but 40% of them didn't know about its role as a purifier in the lake. 2. More than 10% of respondents answered that they were "can not able to stand any more" massive flights of chironomid midges, and about half of them lived within 500 m of the lake shore. The damages "nuisances" were "running laundry or defacing walls (67.1%) and "contamination of food (15.3%)", suggesting that chironomid midges influenced the daily life of the residents. 3. The selected causes of massive flights of chironomid midges were "pollution in Lake Suwa" and "decreases in the numbers of birds and dragonflies" as well as others. This means that the deterioration of the environmental situation around the lake may cause the "nuisance" of chironomid midges. 4. The respondents were more strongly interested in counterplans for the control of the chironomid midges made by administrative authorities than in plans made by each family. 5. "The distance from the lake shore" was the major factor contributing to the impression of chironomid damage. "The occupation of the respondent" was the second important factor. To redirect the insect flights away from the residential area, and to decrease the number of adult midges coming from the lake, are thought to be the most important measures for the resolution of this problem. PMID:1890774

  14. Flaxseed (Linum usitatissimum) supplementation associated with reduced skin test lesional area in horses with Culicoides hypersensitivity

    PubMed Central

    O'Neill, Wendy; McKee, Sharyn; Clarke, Andrew F.

    2002-01-01

    Abstract The purpose of this study was to quantify the effect of flaxseed (Linum usitatissimum) supplementation on the skin test response of atopic horses. Six horses that displayed a positive skin test for allergy to extract from Culicoides sp. participated in the 42-day, placebo-controlled, double-blind, cross-over trial. Results showed that supplementation with flaxseed for 42 days in our experimental horses reduced the mean skin test response to Culicoides sp. This observation was concurrent with a significant decrease in the long-chain saturated fatty acids; behenic acid (22:0) and lignoceric acid (24:0), in the hair of horses receiving flaxseed. There was also a significant decrease in aspartate aminotransferase, and increase in serum glucose in the treatment animals at specific sampling points. It was concluded that; in this small pilot study, flaxseed was able to reduce the lesional area of the skin test response of atopic horses, alter the fatty acid profile of the hair, reduce inflammation, and did not elicit any negative side-effects in the experimental horses. PMID:12418783

  15. Compact genome of the Antarctic midge is likely an adaptation to an extreme environment

    PubMed Central

    Kelley, Joanna L.; Peyton, Justin T.; Fiston-Lavier, Anna-Sophie; Teets, Nicholas M.; Yee, Muh-Ching; Johnston, J. Spencer; Bustamante, Carlos D.; Lee, Richard E.; Denlinger, David L.

    2014-01-01

    The midge, Belgica antarctica, is the only insect endemic to Antarctica, and thus it offers a powerful model for probing responses to extreme temperatures, freeze tolerance, dehydration, osmotic stress, ultraviolet radiation and other forms of environmental stress. Here we present the first genome assembly of an extremophile, the first dipteran in the family Chironomidae, and the first Antarctic eukaryote to be sequenced. At 99 megabases, B. antarctica has the smallest insect genome sequenced thus far. Although it has a similar number of genes as other Diptera, the midge genome has very low repeat density and a reduction in intron length. Environmental extremes appear to constrain genome architecture, not gene content. The few transposable elements present are mainly ancient, inactive retroelements. An abundance of genes associated with development, regulation of metabolism and responses to external stimuli may reflect adaptations for surviving in this harsh environment. PMID:25118180

  16. Evidence incriminating midges (Diptera: Ceratopogonidae) as potential vectors of Leishmania in Australia.

    PubMed

    Dougall, Annette M; Alexander, Bruce; Holt, Deborah C; Harris, Tegan; Sultan, Amal H; Bates, Paul A; Rose, Karrie; Walton, Shelley F

    2011-04-01

    The first autochthonous Leishmania infection in Australia was reported by Rose et al. (2004) and the parasite was characterised as a unique species. The host was the red kangaroo (Macropus rufus) but the transmitting vector was unknown. To incriminate the biological vector, insect trapping by a variety of methods was undertaken at two field sites of known Leishmania transmission. Collected sand flies were identified to species level and were screened for Leishmania DNA using a semi-quantitative real-time PCR. Collections revealed four species of sand fly, with a predominance of the reptile biter Sergentomyia queenslandi (Hill). However, no Leishmania-positive flies were detected. Therefore, alternative vectors were investigated for infection, giving startling results. Screening revealed that an undescribed species of day-feeding midge, subgenus Forcipomyia (Lasiohelea) Kieffer, had a prevalence of up to 15% for Leishmania DNA, with high parasitemia in some individuals. Manual gut dissections confirmed the presence of promastigotes and in some midges material similar to promastigote secretory gel, including parasites with metacyclic-like morphology. Parasites were cultured from infected midges and sequence analysis of the Leishmania RNA polymerase subunit II gene confirmed infections were identical to the original isolated Leishmania sp. Phylogenetic analysis revealed the closest known species to be Leishmania enriettii, with this and the Australian species confirmed as members of Leishmania sensu stricto. Collectively the results strongly suggest that the day-feeding midge (F. (Lasiohelea) sp. 1) is a potential biological vector of Leishmania in northern Australia, which is to our knowledge the first evidence of a vector other than a phlebotomine sand fly anywhere in the world. These findings have considerable implications in the understanding of the Leishmania life cycle worldwide. PMID:21251914

  17. [Construction of PPENK-MIDGE-NLS gene vector and the expression in rat].

    PubMed

    Chen, Xi; Xu, Xuemin; Peng, Xijuan; Jiang, Wei; Yao, Linong

    2015-02-01

    Increasing the production and secretion of endogenous opioid peptide by immune cell can significantly induce myocardial protective effects against ischemia-reperfusion injury. Gene therapy is promising to increase endogenous enkephalin (ENK). However, classical viral and plasmid vectors for gene delivery are hampered by immunogenicity, gene recombination, oncogene activation, the production of antibacterial antibody and changes in physiological gene expression. Minimalistic immunologically defined gene expression (MIDGE) can overcome all the deficients of viral and plasmid vectors. The exon of rat's preproenkephalin (PPENK) gene was amplified by PCR and the fragments were cloned into pEGFP-N1 plasmids. The recombined plasmids were digested with enzymes to obtain a linear vector contained promoter, preproenkephalin gene, RNA stable sequences and oligodesoxy nucleotides (ODNs) added to both ends of the gene vector to protect gene vector from exonuclease degradation. A nuclear localization sequence (NLS) was attached to an ODN to ensure the effective transport to the nucleus and transgene expression. Flow cytometry, laser confocal microscopy and Western blotting demonstrated that PPENK-MIDGE-NLS can transfect leukocyte of rat in vivo, increase the expression of proenkephalin (PENK) in tissue, and the transfection efficiency depends on gene vector's dosage. These results indicate that PPENK-MIDGE-NLS could be an innovative method to protect and treatment of myocardial ischemia-reperfusion injury. PMID:26062347

  18. Does gall midge larvae cause pre-dispersal seed mortality and limit cornflower population growth?

    NASA Astrophysics Data System (ADS)

    Koprdova, Stanislava; Bellanger, Solène; Skuhrovec, Jiří; Darmency, Henri

    2015-11-01

    Many kinds of pests can reduce seed production. Some directly attack seeds before they are released, and some are hosted by the fruit and impact seed ripening and viability indirectly. Pre-dispersal seed mortality may have strong effects on plant population dynamics and evolution. Our goals were to determine to what extent insect-mediated pre-dispersal seed mortality contributes to population-level declines of cornflower, Centaurea cyanus L. We recorded occurrence and abundance of seed-feeding insects on flower heads in twelve cornflower populations. We measured flower head size, number of disc florets, seed production, and seed viability and germination. Larger flower heads had proportionally fewer healthy seeds. Although we observed no visible damage to the C. cyanus seed, the presence of gall midge (Cecidomyiidae) larvae inside the flower head correlated with four times fewer viable seeds. It seems that gall midges could have a significant impact on ovule fertilization, seed abortion and viability of fully developed cornflower seeds. The higher rate of aborted seeds in the presence of gall midge larvae could have been because the larvae extracted resources from the seeds, or because the larvae repelled pollinators. The viability of apparently healthy seeds was 40% lower in flower heads that contained larvae and/or aborted seed. Insect-mediated pre-dispersal mortality could select against evolution toward larger flower head, and have detrimental consequences on seed number, viability and germination, all of which could limit the spread of C. cyanus populations.

  19. Carotenoids in unexpected places: gall midges, lateral gene transfer, and carotenoid biosynthesis in animals.

    PubMed

    Cobbs, Cassidy; Heath, Jeremy; Stireman, John O; Abbot, Patrick

    2013-08-01

    Carotenoids are conjugated isoprenoid molecules with many important physiological functions in organisms, including roles in photosynthesis, oxidative stress reduction, vision, diapause, photoperiodism, and immunity. Until recently, it was believed that only plants, microorganisms, and fungi were capable of synthesizing carotenoids and that animals acquired them from their diet, but recent studies have demonstrated that two arthropods (pea aphid and spider mite) possess a pair of genes homologous to those required for the first step of carotenoid biosynthesis. Absent in all other known animal genomes, these genes appear to have been acquired by aphids and spider mites in one or several lateral gene transfer events from a fungal donor. We report the third case of fungal carotenoid biosynthesis gene homologs in an arthropod: flies from the family Cecidomyiidae, commonly known as gall midges. Using phylogenetic analyses we show that it is unlikely that lycopene cyclase/phytoene synthase and phytoene desaturase homologs were transferred singly to an ancient arthropod ancestor; instead we propose that genes were transferred independently from related fungal donors after divergence of the major arthropod lineages. We also examine variation in intron placement and copy number of the carotenoid genes that may underlie function in the midges. This trans-kingdom transfer of carotenoid genes may represent a key innovation, underlying the evolution of phytophagy and plant-galling in gall midges and facilitating their extensive diversification across plant lineages. PMID:23542649

  20. Using Midges to Assess Past Climate Change in New England and the Canadian Arctic.

    NASA Astrophysics Data System (ADS)

    Francis, D. R.

    2005-05-01

    Paleolimnology has become an important tool in environmental monitoring programs because it can provide baseline data often unavailable by other means. Remains of midges (Chironomidae and other Diptera) have proven useful in paleolimnological biomonitoring of anoxic conditions, nutrient loading, toxic pollutants, and climate change. Analyses of lake sediment cores from Baffin Island highlight faunal changes during the Holocene and indicate warm conditions in the early Holocene. Diversity tends to be low in late-glacial sediments and then increases as climate warms and the landscape develops. In New England lake cores, the much more subtle climate change known as the Little Ice Age can be seen in changes in the chironomid fauna. Using midges as paleoindicators requires modern "training sets" that quantify larval midge distributions across environmental gradients. Surficial sediment samples collected for training sets contain head capsule remains from the whole lake and represent an integrated sample of the modern fauna. These techniques may be useful for investigating chironomid diversity. Typically, head capsule remains can be identified only to genus but since many rapid biological assessment methods take the Chironomidae only to the family level, collection of head capsule remains could be a useful alternative.

  1. Quantifying Dispersal of European Culicoides (Diptera: Ceratopogonidae) Vectors between Farms Using a Novel Mark-Release-Recapture Technique

    PubMed Central

    Kirkeby, Carsten; Bødker, René; Stockmarr, Anders; Lind, Peter; Heegaard, Peter M. H.

    2013-01-01

    Studying the dispersal of small flying insects such as Culicoides constitutes a great challenge due to huge population sizes and lack of a method to efficiently mark and objectively detect many specimens at a time. We here describe a novel mark-release-recapture method for Culicoides in the field using fluorescein isothiocyanate (FITC) as marking agent without anaesthesia. Using a plate scanner, this detection technique can be used to analyse thousands of individual Culicoides specimens per day at a reasonable cost. We marked and released an estimated 853 specimens of the Pulicaris group and 607 specimens of the Obsoletus group on a cattle farm in Denmark. An estimated 9,090 (8,918–9,260) Obsoletus group specimens and 14,272 (14,194–14,448) Pulicaris group specimens were captured in the surroundings and subsequently analysed. Two (0.3%) Obsoletus group specimens and 28 (4.6%) Pulicaris group specimens were recaptured. The two recaptured Obsoletus group specimens were caught at the release point on the night following release. Eight (29%) of the recaptured Pulicaris group specimens were caught at a pig farm 1,750 m upwind from the release point. Five of these were recaptured on the night following release and the three other were recaptured on the second night after release. This is the first time that movement of Culicoides vectors between farms in Europe has been directly quantified. The findings suggest an extensive and rapid exchange of disease vectors between farms. Rapid movement of vectors between neighboring farms may explain the the high rate of spatial spread of Schmallenberg and bluetongue virus (BTV) in northern Europe. PMID:23630582

  2. Biology and efficacy of Aprostocetus (Eulophidae: hymenoptera) as a parasitoid of the blueberry gall midge complex: Dasineura oxycoccana Johnson and Prodiplosis vaccinii (Felt) (Diptera: cecidomyiidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the southeastern US, bud-infesting larvae of two gall midge species, Dasineura oxycoccana (Johnson) and Prodiplosis vaccinii (Felt), destroy from 20% to 80% of the rabbiteye blueberry crop, Vaccinium virgatum Aiton. Fortunately, these midge larvae fall prey to five species of endoparasitic wasps....

  3. Bioconcentration of 5,5',6-trichlorobiphenyl and pentachlorophenol in the midge, Chironomus riparius, as measured by a pharmacokinetic model

    USGS Publications Warehouse

    Lydy, M.J.; Hayton, W.L.; Staubus, A.E.; Fisher, S.W.

    1994-01-01

    A two compartment pharmacokinetic model was developed which describes the uptake and elimination of 5,5',6-trichlorobiphenyl (TCB) and pentachlorophenol (PCP) in the midge, Chironomus riparius. C. riparius were exposed to nominal TCB (2 ??g L-1) and PCP (9 ??g L-1) concentrations during a 16 h static uptake phase. Depuration was determined over approximately 45 h using a flowthrough system without feeding. The uptake clearance (P) was 330 ?? 61 ml g-1 midge h-1 for TCB and 55 ?? 4 ml g-1 midge h-1 for PCP, while measured bioconcentration factors (BCF) were 35,900 and 458 for TCB and PCP, respectively. Overall, the clearance-volume- based pharmacokinetic model predicted BCF values that were consistent with published values as well as with BCF values obtained from the octanol-water partition coefficient (K(ow)).

  4. Critical body residues for lethal and sublethal effects of membrane narcotics in the midge, Chironomus riparius

    SciTech Connect

    Fisher, S.W.; Hwang, H.; Landrum, P.F.

    1995-12-31

    The concept of the critical body residue (CBR) offers a compelling new way to evaluate hazard posed by persistent contaminants such as PCBs. The authors tested the utility of using CBRs for PCBs in an invertebrate species, Chironomus riparius. Acute toxicity (< 10 d) tests were performed with 2nd instar larvae by adding trace amounts of {sup 14}C-labeled PCBs to unlabeled PCBs in amounts sufficient to generate a dose-responsive mortality curve. Because of the limited water solubility of the PCBs tested, it was not possible to produce a toxic tissue concentration via aqueous exposure. This difficulty was overcome by allowing the midges to feed upon contaminated algae (Chlorella vulgaris) which could be loaded with much higher levels of PCBs than would dissolve in water. CBRs for acute toxicity were measured for 3 PCBs; an average CBR of about 1 mmol/kg was determined. If the midge CBRs are lipid normalized, they fall into the range of values that have previously been determined for vertebrates. The authors also evaluated CBRs in midges for a variety of sublethal impairments including development time within a stadium, larval weight and fecundity. A CBR of 1.09 {micro}mol/kg resulted in a significant increase in larval development time and decrease in larval weight for second instar larvae. Tissue residues declined in the third and fourth instars, despite continuing exposure suggesting that the animals developed attenuating mechanisms or that contaminant loss at ecdysis is significant. Despite declining tissue residues throughout the larval instars, fecundity was reduced from 284 eggs/female in controls to 244 eggs/female in animals exposed to the highest sublethal concentration.

  5. Fossil midges (Diptera: Chironomidae) as palaeoclimatic indicators for the Eurasian region

    NASA Astrophysics Data System (ADS)

    Brooks, Stephen J.

    2006-08-01

    Chironomids (non-biting midges) have been used in palaeoenvironmental studies in Eurasia since the 1920s. Initially changes in chironomid assemblages were largely interpreted as a response to changes in trophic status or water depth. It was only with the advent of chironomid-temperature inference models in the early 1990s that their potential as palaeoclimatic indicators was fully exploited. This paper provides a brief review of the pioneering studies but focuses on the most recent advances. Better taxonomic resolution of fossil midges, expansion of modern training sets, use of air temperature data derived from meteorological stations rather than surface-water temperature data, and Bayesian statistical approaches have lead to improvements in the performance of chironomid-temperature transfer functions. Applications of these transfer functions to derive chironomid-inferred temperature estimates from Lateglacial (ca 15,000-11,200 cal. yr BP) and Holocene (11,200 cal. yr BP to Present) sequences from throughout Eurasia are reviewed in this paper. Chironomid-inferred Lateglacial reconstructions closely reflect oxygen isotope records from Greenland ice cores. Holocene reconstructions are less consistent. Some closely follow instrumental records or corroborate other proxy data, while other reconstructions are less successful. As a result of soil development during the Holocene, changes in pH, nutrients, DO and DOC had a greater influence than temperature on the composition of some midge assemblages. One way to mitigate this is through consensus temperature reconstructions from several sites in the same region. The challenge for future workers is for further improvement in taxonomic resolution of sub-fossil chironomid larvae, to improve further the performance of chironomid-temperature inference models, to develop training sets for southern Europe and Russia and to improve our understanding of the ecological responses of chironomids.

  6. Effects of pH on the toxicity and uptake of (14C)lindane in the midge, Chironomus riparius

    SciTech Connect

    Fisher, S.W.

    1985-10-01

    The toxicity of the insecticide, lindane, was measured in the midge, Chironomus riparius, at pH 4, 6, and 8 with the finding that lindane is significantly more toxic at pH 6 than at pH 4 and 8. The higher toxicity of lindane at pH 6 is a product of two factors. First the penetration of the compound into the midge is lower at pH 4 than at pH 6 and 8. Second, a greater percentage of total radioactivity is contributed by parent compound at pH 6.

  7. All stages of the Palaearctic predaceous midge Palpomyia schmidti Goetghebuer, 1934 (Diptera: Ceratopogonidae).

    PubMed

    Szadziewski, Ryszard; Golovatyuk, Larisa V; Sontag, Elżbieta; Urbanek, Aleksandra; Zinchenko, Tatiana D

    2016-01-01

    All stages and the ecology of the Southern Palaearctic Palpomyia schmidti collected from the vicinity of the saline Lake Elton in Russia are described and illustrated. The morphology of larvae and pupae as well as the detailed ecology of the larvae are described for the first time. P. schmidti is a halobiontic biting midge, widely distributed in the steppes and deserts of the Palaearctic region. It is proposed that the Palpomyia schmidti group should include five Holarctic species. P. downesi Grogan & Wirth, 1979 from north-western North America is recognized as a new junior synonym of the Eastern Palaearctic P. tuvae Remm, 1972. New synonymy. PMID:27395743

  8. Oil and PCB interactions on the uptake and excretion in midges

    SciTech Connect

    Meier, P.G.; Rediske, R.R.

    1984-08-01

    The purpose of this study was to examine the effect of sediment oil contamination on the bioaccumulation and excretion of Aroclor 1242 by the chironomid larvae Glyptotendipes barbipes Staeger. This dipteran was chosen as the test organism because it is an important fish food, and also the larva can tolerate a wide range of sediment PCB and oil concentrations. Experiments were conducted under laboratory conditions where midges were exposed to varying concentrations of Aroclor 1242 and mineral oil mixtures. An artificial substrate was chosen over natural sediment because it could be easily prepared in large quantities and accurately contaminated with both PCB and oil.

  9. Characterization of microsatellite loci for the pitcher plant midge, Metriocnemus knabi Coq. (Diptera: Chironomidae).

    PubMed

    Rasic, Gordana; Maxwell, Sheri A; Keyghobadi, Nusha

    2009-09-01

    As a component of the inquiline community of the purple pitcher plant (Sarracenia purpurea), the pitcher plant midge Metriocneus knabi has been the subject of various ecological studies. However, very little is known about its characteristics beyond the larval stage, in particular the dispersal ability of adults. This study presents new molecular tools developed for testing of evolutionary and ecological questions in natural populations of this species. We describe a set of 12 microsatellite loci specific to M. knabi that are sufficiently polymorphic to provide insight into population genetic structure and dispersal patterns. PMID:21564915

  10. A novel mechanism of gall midge resistance in the rice variety Kavya revealed by microarray analysis.

    PubMed

    Rawat, Nidhi; Chiruvuri Naga, Neeraja; Raman Meenakshi, Sundaram; Nair, Suresh; Bentur, Jagadish S

    2012-06-01

    The Asian rice gall midge [Orseolia oryzae (Wood-Mason)] is an important rice pest causing an annual average yield loss of about US $80 million in India. Rice varieties possess several discrete resistance (R) genes conferring resistance against the pest in two distinct ways, i.e., with (HR+ type) or without (HR- type) the expression of hypersensitive reaction (HR). The aim of the present work is to understand the molecular basis of compatible and incompatible (HR- type) rice gall midge interactions between the rice variety Kavya and the two gall midge biotypes: the virulent GMB4M and the avirulent GMB1 using transcriptional microarray gene expression analysis. A large number of differentially expressed genes (602genes in incompatible interaction and 1,330 genes in compatible interaction with at least twofold changes, p value <0.05) was obtained from the microarray analysis that could be grouped into six clusters based on their induction during both or either of the interactions. MapMan software was used for functional characterization of these genes into 13 categories (BINs). Real-time polymerase chain reaction validation of 26 genes selected through the analysis revealed four genes viz. NADPH oxidase, AtrbohF, cinnamoyl-CoA reductase, and von Willebrand factor type A domain containing protein coding genes to be significantly upregulated during the incompatible interaction. But most of the signature genes related to HR+ type resistance like salicylic acid pathway-related genes and disease resistance protein coding genes were downregulated. On the other hand, during the compatible interaction, genes related to primary metabolism and nutrient transport were upregulated and genes for defense and signaling were downregulated. We propose a hypothesis that HR- type of resistance in the rice variety Kavya against gall midge could be due to the constitutive expression of an R gene and a case of extreme resistance which is devoid of cell death. Compatible interaction

  11. Modelling the distribution of outbreaks and Culicoides vectors in Sicily: towards predictive risk maps for Italy.

    PubMed

    Purse, B V; Caracappa, S; Marino, A M F; Tatem, A J; Rogers, D J; Mellor, P S; Baylis, M; Torina, A

    2004-01-01

    Vector (911 light-trap catches from 269 sites) and serological surveillance data were obtained during recent bluetongue (BT) outbreaks in Sicily. The distributions of Culicoides vectors are compared with that of bluetongue virus (BTV) to determine the relative role of different vectors in BTV transmission in Sicily. The 'best' climatic predictors of distribution for each vector species were selected from 40 remotely-sensed variables and altitude at a 1 km spatial resolution using discriminant analysis. These models were used to predict species presence in unsampled pixels across Italy. Although Culicoides imicola, the main European vector, was found in only 12% of sites, there was close correspondence between its spatial distribution and that of the 2000 and 2001 outbreaks. All three candidate vectors C. pulicaris, C. newsteadi and C. obsoletus group were widespread across 2002 outbreak sites but C. newsteadi was significantly less prevalent in outbreak versus non-outbreak sites in Messina and BTV has been isolated from wild-caught adults of both C. pulicaris and C. obsoletus in Italy. The yearly distribution and intensity of outbreaks is attributable to the distribution and abundance of the vectors operating in each year. Outbreaks were few and coastal in 2000 and 2001 due to the low abundance and prevalence of the vector, C. imicola. They were numerous and widespread in 2002, following hand-over of the virus to more prevalent and abundant novel vector species, C. pulicaris and C. obsoletus. Climatic determinants of distribution were species-specific, with those of C. obsoletus group and C. newsteadi predicted by temperature variables, and those of C. pulicaris and C. imicola determined mainly by normalised difference vegetation index (NDVI), a variable correlated with soil moisture, vegetation biomass and productivity. The predicted continuous presence of C. pulicaris along the Appenine mountains, from north to south Italy, suggests BTV transmission may be

  12. Wild swarms of midges linger at the edge of an ordering phase transition

    NASA Astrophysics Data System (ADS)

    Giardina, Irene

    2014-03-01

    The most notable hallmark of collective behavior in biological systems is the emergence of order: individuals synchronize their state, giving the stunning impression that the group behaves as one. Birds flocks, fish schools and mammal herds are just a few common examples of polarized animal groups. Mating swarms of mosquitoes and midges, on the other hand, do not display global order and it is therefore unclear whether swarms are a true instance of collective behavior or a mere epiphenomenon of the independent response of each insect to an environmental stimulus. The crucial task for a group, however, is not simply to achieve an ordered state, but to respond collectively to the environmental stimuli. For this to happen, correlation must be large, namely individuals must be able to influence each other's behavioral changes on a group scale. In this work, we experimentally study wild swarms of midges and find that, despite the lack of collective order, swarms display strong correlation, comparable to that found in highly ordered groups of vertebrates. Correlation is orders of magnitude larger in natural swarms than in random systems, indicating the existence of large clusters of insects responding together. We also find that the total amount of correlation, i.e. the susceptibility, increases sharply with the swarm density, a distinctive mark of an incipient ordering phase transition. Swarms, however, live at the near-critical edge of this transition, never plunging in the ordered phase, suggesting that their size and density are tuned to maximize collective response.

  13. Proteomic evaluation of cadmium toxicity on the midge Chironomus riparius Meigen larvae.

    PubMed

    Lee, Sung-Eun; Yoo, Dong-hun; Son, Jino; Cho, Kijong

    2006-02-01

    Heavy-metal pollution of aquatic ecosystems is a widespread phenomenon after industrial consumption. Whether aquatic organisms are adapted to the heavy-metal pollutants or not, such environmental stress causes changes in physiological responses. In this study, the aquatic midge, Chironomus riparius Meigen, was used to find changes of expression of proteins in relation to cadmium exposure. Dose-response relationships between cadmium concentrations and mortality of 3rd instar midge larvae were observed and the protein levels were compared using PD-Quest after 2-DE. Comparing the intensity of protein spots, 21 proteins decreased and 18 proteins increased in response to cadmium treatment. With increased proteins, three enzymes such as S-adenosylmethionine decarboxylase, O-methyltransferase, and aspartokinase were involved in the glutathione biosynthesis and a key enzyme regulating fatty acid biosynthesis, oleyl-acyl carrier protein thioesterase was also identified. According to the functional classification of decreased levels of proteins, they were involved in energy production, protein fate, nucleotide biosynthesis, cell division, transport and binding, signal transduction, and fatty acid and phospholipid metabolism in the cell. In addition, phenol hydroxylase, thioesterase, zinc metalloprotease, and aspartate kinase were newly expressed after cadmium exposure at the concentration of the LC(10 )value. Therefore, these proteins seem to be potential biomarkers for cadmium exposure in the aquatic ecosystems. PMID:16372273

  14. TOXICITY OF SEVERAL FUNGICIDES FOR ORANGE WHEAT BLOSSOM MIDGE, SITODIPLOSIS MOSELLANA (GÉHIN) (DIPTERA: CECIDOMYIIDAE).

    PubMed

    Chavalle, S; Jansen, J-P; San Martin y Gomez, G; De Proft, M

    2015-01-01

    The orange wheat blossom midge, Sitadiplosis mosellano (Géhin) (Diptera: Cecidomyiidae), can cause severe losses in wheat grain yield and quality. This pest is known to be susceptible to many insecticides, but various field observations have suggested that some fungicides could also significantly affect S. mosellana. In order to confirm these field observations, the effect on adult midges of several fungicides commonly applied to wheat crops was investigated in the laboratory and in small plots in the field. In each experiment, the fungicides were compared with a positive (insecticide) and a negative control (water). Four fungicides were assessed in the laboratory, each with five doses based on basis of a tenfold dilution starting at the field-recommended dose. The mortality rate was evaluated after 24 hours and the lethal dose 50% (LD50) was determined for each product. In the field, six fungicides were tested at the recommended dose. The effect of each product was compared on the basis of the number of S. mosellana adults caught alive with an insect vacuum sampler (Vortis®) on the morning after the treatments. Both experiments showed a significant effect of several fungicides tested on S. mosellana adults. Chlorothalonil was not toxic for S. mosellana, but tebuconazole, fluxapyroxad and azoxystrobin all induced significant mortality rates. PMID:27145574

  15. Joint toxicity of triazine herbicides and organophosphate insecticides to the midge Chironomus tentans.

    PubMed

    Schuler, L J; Trimble, A J; Belden, J B; Lydy, M J

    2005-08-01

    A series of recent studies demonstrated that the triazine herbicide atrazine, although not itself acutely toxic, potentiated the toxicity of certain organophosphate insecticides (OPs) to the midge Chironomus tentans. In the current study, a series of triazine herbicides and triazine herbicide degradation products were tested to determine if other triazines potentiate OP toxicity to midges. Chlorpyrifos and diazinon were the OPs tested. Toxicity tests were conducted using a factorial design and analysis of variance to statistically determine if each triazine had an effect on expected toxicity. Log-probit procedures were also used to evaluate the magnitude of change in median effective concentration (EC50) values during coexposure with each triazine. All of the triazine herbicides tested (atrazine, simazine, cyanazine, and hexazinone) were capable of potentiating the toxicity of the OPs, whereas the degradation products (s-triazine, deethylatrazine, and deisopropylatrazine) had less effect. In most cases, a triazine concentration of 100 microg/L was necessary to significantly increase OP toxicity, and higher concentrations of triazine caused a greater degree of potentiation. Changes in EC50 values ranged from no change to a 2.5-fold increase in toxicity. Generally, EC50 values changed by less than a factor of 2, indicating that the effect may be of limited concern in regard to future risk assessments of OPs. PMID:15988628

  16. Aquaporins in the antarctic midge, an extremophile that relies on dehydration for cold survival.

    PubMed

    Goto, Shin G; Lee, Richard E; Denlinger, David L

    2015-08-01

    The terrestrial midge Belgica antarctica relies extensively on dehydration to survive the low temperatures and desiccation stress that prevail in its Antarctic habitat. The loss of body water is thus a critical adaptive mechanism employed at the onset of winter to prevent injury from internal ice formation; a rapid mechanism for rehydration is equally essential when summer returns and the larva resumes the brief active phase of its life. This important role for water movement suggests a critical role for aquaporins (AQPs). Recent completion of the genome project on this species revealed the presence of AQPs in B. antarctica representing the DRIP, PRIP, BIB, RPIP, and LHIP families. Treatment with mercuric chloride to block AQPs also blocks water loss, thereby decreasing cell survival at low temperatures. Antibodies directed against mammalian or Drosophila AQPs suggest a wide tissue distribution of AQPs in the midge and changes in protein abundance in response to dehydration, rehydration, and freezing. Thus far, functional studies have been completed only for PRIP1. It appears to be a water-specific AQP, but expression levels are not altered by dehydration or rehydration. Functional assays remain to be completed for the additional AQPs. PMID:26338869

  17. Evaluation of ULV naled applied simultaneously against caged adult Aedes taeniorhynchus and Culicoides furens.

    PubMed

    Linley, J R; Parsons, R E; Winner, R A

    1988-09-01

    Two experiments were conducted to test application of ULV naled against adult Aedes taeniorhynchus and Culicoides furens exposed simultaneously in cages hung on poles at selected heights and distances from the spray source. ULV spray was released at 0.14 oz active ingredient/acre, droplet size 13.5 micron mmd. In both experiments, insecticide largely carried over the first poles. The greatest mortality occurred at the second pole position, 18.3 and 25.7 m, respectively, from the spray origin, and diminished progressively with increasing distance. Cages at the highest elevation (183 cm) showed the greatest mortality, while those near the ground (15 cm) were substantially less affected. Regression analysis showed that 70% control or better was attained up to a distance (beyond a line 10 m from the release point) of 23 m in the case of Ae. taeniorhynchus and 18 m in the case of C. furens. ULV naled, applied as described, was not particularly effective for control of Ae. taeniorhynchus and C. furens, and was poor for insects exposed in low vegetation. PMID:3199122

  18. Combination of MIDGE-Th1 DNA vaccines with the cationic lipid SAINT-18: studies on formulation, biodistribution and vector clearance.

    PubMed

    Endmann, Anne; Oswald, Detlef; Riede, Oliver; Talman, Eduard G; Vos, Roelien E; Schroff, Matthias; Kleuss, Christiane; Ruiters, Marcel H J; Juhls, Christiane

    2014-06-01

    We have previously shown that the combination of MIDGE-Th1 DNA vectors with the cationic lipid SAINT-18 increases the immune response to the encoded antigen in mice. Here, we report on experiments to further optimize and characterize this approach. We evaluated different formulations of MIDGE-Th1 vectors with SAINT-18 by assessing their influence on the transfection efficiency in cell culture and on the immune response in mice. We found that high amounts of SAINT-18 in formulations with a w/w ratio MIDGE Th1/SAINT-18 of 1:4.8 are beneficial for cell transfection in vitro. In contrast, the formulation of HBsAg-encoding MIDGE-Th1 DNA vectors with the lowest amount of SAINT-18 (w/w ratio MIDGE Th1/SAINT-18 of 1:0.5) resulted in the highest serum IgG1 and IgG2a levels after intradermal immunization of mice. Consequently, latter formulation was selected for a comparative biodistribution study in rats. Following intradermal administration of both naked and formulated MIDGE-Th1 DNA, the vectors localized primarily at the site of injection. Vector DNA levels decreased substantially over the two months duration of the study. When administered in combination with SAINT-18, the vectors were found in significantly higher amounts in draining lymph nodes in comparison to administration of naked MIDGE-Th1 DNA. We propose that the high immune responses induced by MIDGE-Th1/SAINT-18 lipoplexes are mediated by enhanced transfection of cells in vivo, resulting in stronger antigen expression and presentation. Importantly, the combination of MIDGE-Th1 vectors with SAINT-18 was well tolerated in mice and rats and is expected to be safe in human clinical applications. PMID:24681271

  19. Pyrosequencing-Based Transcriptome Analysis of the Asian Rice Gall Midge Reveals Differential Response during Compatible and Incompatible Interaction

    PubMed Central

    Sinha, Deepak Kumar; Nagaraju, Javaregowda; Tomar, Archana; Bentur, Jagadish S.; Nair, Suresh

    2012-01-01

    The Asian rice gall midge (Orseolia oryzae) is a major pest responsible for immense loss in rice productivity. Currently, very little knowledge exists with regard to this insect at the molecular level. The present study was initiated with the aim of developing molecular resources as well as identifying alterations at the transcriptome level in the gall midge maggots that are in a compatible (SH) or in an incompatible interaction (RH) with their rice host. Roche 454 pyrosequencing strategy was used to develop both transcriptomics and genomics resources that led to the identification of 79,028 and 85,395 EST sequences from gall midge biotype 4 (GMB4) maggots feeding on a susceptible and resistant rice variety, TN1 (SH) and Suraksha (RH), respectively. Comparative transcriptome analysis of the maggots in SH and RH revealed over-representation of transcripts from proteolysis and protein phosphorylation in maggots from RH. In contrast, over-representation of transcripts for translation, regulation of transcription and transcripts involved in electron transport chain were observed in maggots from SH. This investigation, besides unveiling various mechanisms underlying insect-plant interactions, will also lead to a better understanding of strategies adopted by insects in general, and the Asian rice gall midge in particular, to overcome host defense. PMID:23202939

  20. Aprostocetus xiphopunctus Sampson nov. sp. (Hymenoptera: Eulophidea): A new natural ememy of a gall midge complex (Diptera: Cecidomyiidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new endoparasitoid kills 40 – 100% of Dasineura oxycoccana and Prodiplosis vaccinii larvae, pest midges that seriously reduce blueberry yield. Female wasps methodically probe leaf buds for host larvae and their parasitism can be more effective than chemical control. With each successive molt, host...

  1. [Ceratopogonidae (Diptera) of the Congolese Mayombe. I. Daily pattern of the biting activity of female Culicoides grahamii Austen, 1909].

    PubMed

    Vattier-Bernard, G; Itoua, A; Trouillet, J; Lallemant, M

    1986-01-01

    Owing to appropriate sampling methods, the study of the daily pattern of biting of female "Culicoides grahamii Austen, 1909" was achieved in the Congolese Mayombe. It was discovered that this pattern was rhythmical in close connection with the sunrise and sunset. Many climatic parameters were simultaneously studied (temperature, hygrometry, brightness). This starting factor of this rhythmical pattern seems to be a brightness which agrees to a total shortwave radiation on the ground, equal or inferior to 25 cal x m-2 x h-1. It seems that the temperature does not play any role. PMID:3813421

  2. Modelling the distributions of Culicoides bluetongue virus vectors in Sicily in relation to satellite-derived climate variables.

    PubMed

    Purse, B V; Tatem, A J; Caracappa, S; Rogers, D J; Mellor, P S; Baylis, M; Torina, A

    2004-06-01

    Surveillance data from 268 sites in Sicily are used to develop climatic models for prediction of the distribution of the main European bluetongue virus (BTV) vector Culicoides imicola Kieffer (Diptera: Ceratopogonidae) and of potential novel vectors, Culicoides pulicaris Linnaeus, Culicoides obsoletus group Meigen and Culicoides newsteadi Austen. The models containing the 'best' climatic predictors of distribution for each species, were selected from combinations of 40 temporally Fourier-processed remotely sensed variables and altitude at a 1 km spatial resolution using discriminant analysis. Kappa values of around 0.6 for all species models indicated substantial levels of agreement between model predictions and observed data. Whilst the distributions of C. obsoletus group and C. newsteadi were predicted by temperature variables, those of C. pulicaris and C. imicola were determined mainly by normalized difference vegetation index (NDVI), a variable correlated with soil moisture and vegetation biomass and productivity. These models were used to predict species presence in unsampled pixels across Italy and for C. imicola across Europe and North Africa. The predicted continuous presence of C. pulicaris along the appenine mountains, from north to south Italy, suggests BTV transmission may be possible in a large proportion of this region and that seasonal transhumance (seasonal movement of livestock between upland and lowland pastures) even in C. imicola-free areas should not generally be considered safe. The predicted distribution of C. imicola distribution shows substantial agreement with observed surveillance data from Greece and Iberia (including the Balearics) and parts of mainland Italy (Lazio, Tuscany and areas of the Ionian coast) but is generally much more restricted than the observed distribution (in Sardinia, Corsica and Morocco). The low number of presence sites for C. imicola in Sicily meant that only a restricted range of potential C. imicola habitats were

  3. Entomological research on the vectors of bluetongue disease and the monitoring of activity of Culicoides in the Prishtinë region of Kosova.

    PubMed

    Berisha, Betim; Goga, Izedin; Hulaj, Beqë; Çaushi, Driton; Sherifi, Kurtesh; Wilsmore, Anthony J; Taylor, William P

    2010-01-01

    Clinical bluetongue (BT) caused by BT virus serotype 9 (BTV-9) was observed in Kosova in 2001 and, although subsequently no further clinical cases was diagnosed, its continuing presence has been demonstrated by serological tests in cattle, sheep and goats. In this study, light traps were placed in stables near Prishtinë to identify possible vectors of BTV in Kosova. Samples were collected from October 2004 until the end of 2006. Culicoides were identified and speciated and results were plotted against temperature data. Samples contained Obsoletus and Pulicaris Complexes but not C. imicola. The first specimens of Culicoides were collected in April and they continued to be detected until November. Generally, Obsoletus Complex was present in the largest numbers, with the exception of the middle of the year when the Pulicaris Complex predominated. The number of Culicoides trapped was directly linked to temperature (p<0.05) and records indicated that Culicoides activity ceased when minimum temperatures fell below 0°C; activity recommenced when minimum temperatures rose to approximately 6°C. These results indicate that there was a lack of a vector for BTV during winter for a period lasting approximately five months. PMID:21132628

  4. A comparison of a new centrifuge sugar flotation technique with the agar method for the extraction of immature Culicoides (Diptera: Ceratopogonidae) life stages from salt marsh soils.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two sampling techniques, agar extraction (AE) and centrifuge sugar flotation extraction (CSFE) were compared to determine their relative efficacy to recover immature stages of Culicoides spp from salt marsh substrates. Three types of samples (seeded with known numbers of larvae, homogenized field s...

  5. Refining methods for conducting long-term sediment and water toxicity tests with Chironomus dilutus: Formation of a midge chronic testing work group

    EPA Science Inventory

    Standard methods have been established by USEPA, ASTM International, Environment Canada and Organization for Economic Cooperation and Development for conducting sediment toxicity tests with various species of midges including Chironomus dilutus. Short-term 10-day exposures are ty...

  6. Allergen-Specific Cytokine Polarization Protects Shetland Ponies against Culicoides obsoletus-Induced Insect Bite Hypersensitivity.

    PubMed

    Meulenbroeks, Chantal; van der Lugt, Jaco J; van der Meide, Nathalie M A; Willemse, Ton; Rutten, Victor P M G; Zaiss, Dietmar M W

    2015-01-01

    The immunological mechanisms explaining development of an allergy in some individuals and not in others remain incompletely understood. Insect bite hypersensitivity (IBH) is a common, seasonal, IgE-mediated, pruritic skin disorder that affects considerable proportions of horses of different breeds, which is caused by bites of the insect Culicoides obsoletus (C. obsoletus). We investigated the allergen-specific immune status of individual horses that had either been diagnosed to be healthy or to suffer of IBH. Following intradermal allergen injection, skin biopsies were taken of IBH-affected and healthy ponies and cytokine expression was determined by RT-PCR. In addition, allergen-specific antibody titers were measured and cytokine expression of in vitro stimulated, allergen-specific CD4 T-cells was determined. 24 hrs after allergen injection, a significant increase in mRNA expression of the type-2 cytokine IL-4 was observed in the skin of IBH-affected Shetland ponies. In the skin of healthy ponies, however, an increase in IFNγ mRNA expression was found. Analysis of allergen-specific antibody titers revealed that all animals produced allergen-specific antibodies, and allergen-specific stimulation of CD4 T-cells revealed a significant higher percentage of IFNγ-expressing CD4 T-cells in healthy ponies compared to IBH-affected ponies. These data indicate that horses not affected by IBH, in contrast to the so far established dogma, are not immunologically ignorant but have a Th1-skewed allergen-specific immune response that appears to protect against IBH-associated symptoms. To our knowledge this is the first demonstration of a natural situation, in which an allergen-specific immune skewing is protective in an allergic disorder. PMID:25901733

  7. Sensitivity of midge larvae of Chironomus tentans Fabricius (Diptera Chironomidae) to heavy metals

    SciTech Connect

    Khangarot, B.S.; Ray, P.K.

    1989-03-01

    The discharge of heavy metals into the natural waters has numerous obvious impacts on physical, chemical and biological parameters of aquatic ecosystem. Bioassay tests are important steps in establishing appropriate water quality criteria and standards for diverse use of ponds, lakes, streams and river waters. Therefore, the acute toxicities of various heavy metals to water flea Daphnia magna, and snail Lymnaea acuminata, and toad tadpoles Bufo mentanostictus have been reported from the authors' laboratory. Chironomid larvae might be particularly useful as indicators of water quality because they are widely distributed in freshwater systems and often from diverse communities within particular habitat. The aim of this study was to determine the acute toxicity of ten heavy metals to the midge larvae Chironomus tentans Fabricius, which forms an important link in aquatic food chain(s).

  8. A cysteine-clamp gene drives embryo polarity in the midge Chironomus*

    PubMed Central

    Klomp, Jeff; Athy, Derek; Kwan, Chun Wai; Bloch, Natasha I.; Sandmann, Thomas; Lemke, Steffen; Schmidt-Ott, Urs

    2015-01-01

    In the common fruit fly Drosophila, head formation is driven by a single gene, bicoid, which generates head-to-tail polarity of the main embryonic axis. Bicoid deficiency results in embryos with tail-to-tail polarity and no head. However, most insects lack bicoid, and the molecular mechanism for establishing head-to-tail polarity is poorly understood. We have identified a gene that establishes head-to-tail polarity of the mosquito-like midge, Chironomus riparius. This gene, named panish, encodes a cysteine-clamp DNA binding domain and operates through a different mechanism than bicoid. This finding, combined with the observation that the phylogenetic distributions of panish and bicoid are limited to specific families of flies, reveals frequent evolutionary changes of body axis determinants and a remarkable opportunity to study gene regulatory network evolution. PMID:25953821

  9. A Key to the Pupal Exuviae of the Midges (Diptera: Chironomidae) of Everglades National Park, Florida

    USGS Publications Warehouse

    Jacobsen, Richard E.

    2008-01-01

    A key has been developed for identifying the pupal exuviae of 132 taxa of chironomid midges collected in Everglades National Park, as well as 18 additional species from freshwater habitats adjacent to the Park. Descriptions and illustrations are based upon voucher specimens from extensive collections of chironomid pupal exuviae for faunal surveys and biomonitoring research conducted in ENP and surrounding freshwater areas from 1998 to 2007. The key includes taxonomic comments for confirming identifications, as well as brief summaries of the distribution and ecology of each species in southern Florida waters. Information is also provided on the morphology of chironomid pupal exuviae, recommended references for identifying pupal exuviae, techniques for making slides, and methods to confirm proper identification.

  10. Embryo development. A cysteine-clamp gene drives embryo polarity in the midge Chironomus.

    PubMed

    Klomp, Jeff; Athy, Derek; Kwan, Chun Wai; Bloch, Natasha I; Sandmann, Thomas; Lemke, Steffen; Schmidt-Ott, Urs

    2015-05-29

    In the fruit fly Drosophila, head formation is driven by a single gene, bicoid, which generates head-to-tail polarity of the main embryonic axis. Bicoid deficiency results in embryos with tail-to-tail polarity and no head. However, most insects lack bicoid, and the molecular mechanism for establishing head-to-tail polarity is poorly understood. We have identified a gene that establishes head-to-tail polarity of the mosquito-like midge, Chironomus riparius. This gene, named panish, encodes a cysteine-clamp DNA binding domain and operates through a different mechanism than bicoid. This finding, combined with the observation that the phylogenetic distributions of panish and bicoid are limited to specific families of flies, reveals frequent evolutionary changes of body axis determinants and a remarkable opportunity to study gene regulatory network evolution. PMID:25953821

  11. Moonlight receptor of the "1-h-midge" Clunio marinus studied by micro-XRF

    NASA Astrophysics Data System (ADS)

    Falkenberg, G.; Fleissner, Ge; Neumann, D.; Wellenreuther, G.; Alraun, P.; Fleissner, Gue

    2013-10-01

    Melanin is a pigment widely occurring in animals, plants, fungi and algae. It does not only colour skin, hair and eyes but serves mainly as photoprotectant and prevents overload with minerals induced by inflammations, infections and degenerative diseases. Therefore, the mechanisms underlying melanisation gained increasing interest in the field of biomedical research and clinic. So far, the processes of melanogenesis are only partly analysed, nearly nothing is known on a putative switch between melanins of different types. Here we offer a model organism to study these mechanisms as part of a naturally cycling change of transparency of the retinal shielding pigment. A marine midge, Clunio marinus, living in coastal regions, underlies a complex timing of its development by solar and lunar climatic periodicities, which synchronise biological clocks. The question was how the animals can discriminate changing sunlight from moonlight intensities. For the first time, we could show a "moonlight window" in the larval ocelli of this midge, and propose a hypothesis on the underlying mechanisms. Driven by a lunar clock the image forming ocelli become transparent and convert during moonlit nights to a sensitive photometer, which can record the dynamics of environmental light. High resolution X-ray fluorescence (XRF) measurements of the distribution of trace minerals in single melanosomes combined with their fine structural details in various states of the lunar cycle provide a first insight into the enzymatic pathways for the generation of a dark melanin (like eumelanin) and a light coloured melanin (like phaeomelanin). Essential advantage of this approach is the spatial and temporal resolution of the metals associated with melanisation processes, which could never before be demonstrated in these details. The data may stimulate further research projects in biomedicine.

  12. Midge-Inferred Temperatures from Three Interglacial Periods in the Eastern Canadian Arctic

    NASA Astrophysics Data System (ADS)

    Axford, Y.; Briner, J. P.; Francis, D. R.; Baker, G.; Miller, G. H.

    2005-12-01

    Lake sediments recovered from a Canadian Arctic lake are providing a rare opportunity to reconstruct Holocene, last interglacial, and earlier temperature changes at centennial to decadal resolution. Lake CF8 (informal name) is a small (0.5 km2) lake situated on an inter-fjord lowland in northeastern Baffin Island at 70o N latitude. Sediment cores from Lake CF8 contain three organic lake sediment units, separated by non-lacustrine sands. Radiocarbon ages from the uppermost organic unit span the entire Holocene. The middle organic unit is beyond the limit of radiocarbon dating. Comparison with a similar lacustrine record from Fog Lake, Baffin Island, indicates that this middle unit most likely records the last interglacial (Eemian) period. The lowest organic unit was only partially recovered, but may record the late stages of the penultimate interglacial. Subfossil midges (Chironomidae) are abundant and well-preserved throughout the organic sediments, providing a quantitative means for temperature reconstruction. Midge-based temperature reconstructions indicate that summer temperatures at Lake CF8 surpassed modern values by 10 cal kyr BP. Summer temperatures during the first half of the Holocene were as much as 5oC warmer than present. Similarly, the early part of the last interglacial was several degrees warmer than the latter part of the period. The bottommost lake sediments we recovered, which were presumably deposited during the late stages of a prior interglacial period, record summer temperatures similar to those of the latter parts of the Holocene and last interglacial. The magnitude of early Holocene and last interglacial warmth at this high-latitude site lends support to concerns about Arctic amplification of future warming.

  13. An inducible HSP70 gene from the midge Chironomus dilutus: Characterization and transcription profile under environmental stress

    USGS Publications Warehouse

    Karouna-Renier, N. K.; Rao, K.R.

    2009-01-01

    In the present study, we identified and characterized an inducible heat shock protein 70 (HSP70) from the midge Chironomus dilutus and investigated the transcriptional profile of the gene under baseline and environmentally stressful conditions. Using real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR), we observed increased expression of CD-HSP70-1 in response to both heat shock and copper stress. We also investigated the expression of this gene during midge development. All C. dilutus developmental stages expressed CD-HSP70-1 under normal conditions, although at extremely low levels. Phylogenetic analysis of the amino acid sequence demonstrated distinct clustering of this gene with inducible HSP70s from other insect species. ?? 2008 The Authors.

  14. Assessing the toxicity of dodecylbenzene sulfonate to the midge Chironomus riparius using body residues as the dose metric.

    PubMed

    Hwang, Haejo; Fisher, Susan W; Kim, Kyeok; Landrum, Peter F; Larson, Robert J; Versteeg, Donald J

    2003-02-01

    Dodecylbenzene sulfonate (DBS) is a component of linear alkylbenzene sulfonate (LAS), an anionic surfactant, mainly used in household detergents. Due to the large quantity of DBS in use, there is concern over adverse environmental effects. This work examined the toxicokinetics and toxicity of the 2-phenyl isomer of dodecylbenzene sulfonate in 4-d, 10-d, and partial life-cycle tests on the midge, Chironomus riparius, exposed to aqueous solutions. Toxicokinetics were determined in 10-d uptake and 5-d elimination tests. The toxicokinetics were based on parent compound concentration in water and yielded an uptake coefficient (ku) of 17.5 (14.87-20.20) ml/g/h, an elimination rate constant (ke) of 0.073 (0.062-0.085) per h, a bioconcentration factor (BCF) of 56 to 240, and a half-life (t 1/2) of 9.5 (8.0-11.0) h. Biotransformation measurements did not reveal evidence for DBS metabolism. Thus, body residues, determined in the toxicity study, represent parent compound. In toxicity tests, 4- and 10-d LR50s (the body residue required to cause 50% mortality) in live midges were 0.72 (0.65-0.79) and 0.18 (0.08-0.42) mmol/kg, respectively. Thirty-day LR50s were 0.18 (0.09-1.64) and 0.21 (0.15-0.39) mmol/kg in duplicate studies. Of the sublethal endpoints, only developmental time increase was significant, with the lowest-observed-effect residues of 0.085 (0.067-0.105) and 0.100 (0.087-0.114) mmol/kg for male and female midges, respectively. Deformities in surviving larvae were also observed as chronic responses for body residues exceeding the 30-d LR50. The body residues required for mortality suggest that DBS acts like a polar narcotic in the midge. PMID:12558161

  15. From Midges to Spiders: Mercury Biotransport in Riparian Zones Near the Buffalo River Area of Concern (AOC), USA.

    PubMed

    Pennuto, C M; Smith, M

    2015-12-01

    Riparian communities can receive environmental contaminants from adjacent aquatic 'donor' habitats. We investigated mercury biotransport from aquatic to terrestrial habitats via aquatic insect emergence and uptake by riparian spiders at sites within and upstream of the Buffalo River Area of Concern (AOC), a site with known sediment Hg contamination. Mercury concentration in emerging midges was roughly 10× less than contaminated sediment levels with the AOC, but biomagnification factors from midges to spiders ranged from 2.0 to 2.65 between sites. There was a significantly negative body mass:total mercury relationship in spiders (p < 0.001), indicating that mercury depuration is rapid or tissue dilution occurs in these riparian predators. Spiders contained significantly more mercury than their midge prey and spiders upstream of the AOC had higher mercury concentrations than spiders from within the AOC. Collectively, these data indicate that riparian spiders can be good mercury sentinels in urban environments, and that riparian communities upstream from the AOC may be at greater risk to mercury than has been previously considered. PMID:26387024

  16. Efficient shedding of accumulated metals during metamorphosis in metal-adapted populations of the midge Chironomus riparius

    SciTech Connect

    Groenendijk, D.; Kraak, M.H.S.; Admiraal, W. . Dept. of Aquatic Ecology and Ecotoxicology)

    1999-06-01

    Metal accumulation and loss during metamorphosis were investigated in Chironomus riparius populations in a metal contaminated lowland river. Cadmium and zinc levels were measured in imagoes and larvae at reference and metal-exposed sites. It was hypothesized that the relationship between metal concentrations in biota and environmental compartments would be influenced by the presence of metal-adapted chironomids. In contrast to the large interpopulation differences in larval body burdens of cadmium, body burdens in imagoes vanished to background levels for all midge populations. This indicated that any cadmium accumulated in larval stages was lost during metamorphosis. This nearly 100% efficiency in shedding of cadmium is most likely caused by an increased metal handling capacity present in exposed midges. In agreement with the cadmium measurements, larval body burdens of zinc showed also highly significant interpopulation differences. In contrast with the cadmium values, however, body burdens of zinc in imagoes showed highly significant interpopulation differences and differences were even recorded between the two exposed sites, indicating interpopulation differences in shedding capacity for zinc. It is concluded that the highly efficient shedding of accumulated metals reflected the metal adaptation recorded in earlier studies of metal-exposed C. riparius populations from the River Dommel. Based on the differences in metal accumulation and the differences found in shedding of metals between the two exposed midge populations, it was concluded that population differentiation due to metal stress is a gradual process rather than an all-or-nothing situation.

  17. A wind density model to quantify the airborne spread of Culicoides species during north-western Europe bluetongue epidemic, 2006.

    PubMed

    Hendrickx, Guy; Gilbert, Marius; Staubach, Christoph; Elbers, Armin; Mintiens, Koen; Gerbier, Guillaume; Ducheyne, Els

    2008-10-15

    Increased transport and trade as well as climate shifts play an important role in the introduction, establishment and spread of new pathogens. Arguably, the introduction of bluetongue virus (BTV) serotype 8 in Benelux, Germany and France in 2006 is such an example. After its establishment in receptive local vector and host populations the continued spread of such a disease in a suitable environment will mainly depend on movement of infected vectors and animals. In this paper we explore how wind models can contribute to explain the spread of BTV in a temperate eco-climatic setting. Based on previous work in Greece and Bulgaria filtered wind density maps were computed using data from the European Centre for Medium-Range Weather Forecasts (ECMWF). Six hourly forward wind trajectories were computed at pressure levels of 850 hPa for each infected farm as from the recorded onset of symptoms. The trajectories were filtered to remove wind events that do not contribute to possible spread of the vector. The suitable wind events were rastered and aggregated on a weekly basis to obtain weekly wind density maps. Next to this, cumulated wind density maps were also calculated to assess the overall impact of wind dispersal of vectors. A strong positive correlation was established between wind density data and the horizontal asymmetrical spread pattern of the 2006 BTV8 epidemic. It was shown that short (<5 km), medium (5-31 km) and long (>31 km) distance spread had a different impact on disease spread. Computed wind densities were linked to the medium/long-distance spread whilst short range spread was mainly driven by active Culicoides flight. Whilst previous work in the Mediterranean basin showed that wind driven spread of Culicoides over sea occurred over distances of up to 700 km, this phenomenon was not observed over land. Long-distance spread over land followed a hopping pattern, i.e. with intermediary stops and establishment of local virus circulation clusters at distances of

  18. Sensitization of skin mast cells with IgE antibodies to Culicoides allergens occurs frequently in clinically healthy horses.

    PubMed

    Wagner, Bettina; Miller, William H; Erb, Hollis N; Lunn, D Paul; Antczak, Douglas F

    2009-11-15

    IgE antibodies are mediators of mast cell degranulation during allergic diseases. The binding of IgE to its high-affinity IgE receptor on mast cell surfaces is called "sensitization" and precedes the development of clinical allergy. Previously, intradermal injection of anti-IgE or the anti-IgG(T) antibody CVS40 induced immediate skin reactions in horses. This suggested that both IgE and IgG(T) sensitize equine skin mast cells. Here, we investigated sensitization to allergen and with IgE or IgG(T) in clinically healthy horses of different age groups. In addition, immediate skin reactions to Culicoides were determined by intradermal testing in non-allergic horses. A total of 14% of the young horses 1-3 years old and 38% of the adult animals showed skin reaction to Culicoides allergen extract. Sensitization with IgE and IgG(T) was evaluated in skin mast cells and peripheral blood basophils to determine whether sensitization with IgG(T) preceded that with IgE in young horses. Anti-IgE stimulated immediate skin reactions in 18 of 21 young horses, but only 7 of them reacted to the anti-IgG(T) antibody CVS40. The equine IgG(T) fraction is composed of IgG3 and IgG5. We used several newly developed monoclonal antibodies to IgG3 and IgG5 for intradermal testing to improve our understanding about the mast cell reaction induced by the anti-IgG(T) antibody CVS40. None of these antibodies induced a skin reaction in young or adult horses. To determine sensitization with IgE in neonates and foals at 6 and 12 weeks of age an in vitro histamine release assay was performed using peripheral blood cells. The histamine concentration released by anti-IgE stimulation from foal basophils increased between birth and 12 weeks of age, while almost no histamine release was observed after anti-IgG(T) treatment of the cells. In summary, IgE was the major immunoglobulin involved in the sensitization of mast cells and basophils in horses at various ages. IgG(T) antibodies did not play a major role

  19. Comparative genome sequencing reveals genomic signature of extreme desiccation tolerance in the anhydrobiotic midge.

    PubMed

    Gusev, Oleg; Suetsugu, Yoshitaka; Cornette, Richard; Kawashima, Takeshi; Logacheva, Maria D; Kondrashov, Alexey S; Penin, Aleksey A; Hatanaka, Rie; Kikuta, Shingo; Shimura, Sachiko; Kanamori, Hiroyuki; Katayose, Yuichi; Matsumoto, Takashi; Shagimardanova, Elena; Alexeev, Dmitry; Govorun, Vadim; Wisecaver, Jennifer; Mikheyev, Alexander; Koyanagi, Ryo; Fujie, Manabu; Nishiyama, Tomoaki; Shigenobu, Shuji; Shibata, Tomoko F; Golygina, Veronika; Hasebe, Mitsuyasu; Okuda, Takashi; Satoh, Nori; Kikawada, Takahiro

    2014-01-01

    Anhydrobiosis represents an extreme example of tolerance adaptation to water loss, where an organism can survive in an ametabolic state until water returns. Here we report the first comparative analysis examining the genomic background of extreme desiccation tolerance, which is exclusively found in larvae of the only anhydrobiotic insect, Polypedilum vanderplanki. We compare the genomes of P. vanderplanki and a congeneric desiccation-sensitive midge P. nubifer. We determine that the genome of the anhydrobiotic species specifically contains clusters of multi-copy genes with products that act as molecular shields. In addition, the genome possesses several groups of genes with high similarity to known protective proteins. However, these genes are located in distinct paralogous clusters in the genome apart from the classical orthologues of the corresponding genes shared by both chironomids and other insects. The transcripts of these clustered paralogues contribute to a large majority of the mRNA pool in the desiccating larvae and most likely define successful anhydrobiosis. Comparison of expression patterns of orthologues between two chironomid species provides evidence for the existence of desiccation-specific gene expression systems in P. vanderplanki. PMID:25216354

  20. Massive Shift in Gene Expression during Transitions between Developmental Stages of the Gall Midge, Mayetiola Destructor

    PubMed Central

    Chen, Ming-Shun; Liu, Sanzhen; Wang, Haiyan; Cheng, Xiaoyan; El Bouhssini, Mustapha; Whitworth, R. Jeff

    2016-01-01

    Mayetiola destructor is a destructive pest of wheat and has six developmental stages. Molecular mechanisms controlling the transition between developmental stages remain unknown. Here we analyzed genes that were expressed differentially between two successive developmental stages, including larvae at 1, 3, 5, and 7 days, pupae, and adults. A total of 17,344 genes were expressed during one or more of these studied stages. Among the expressed genes, 38–68% were differently expressed between two successive stages, with roughly equal percentages of up- and down-regulated genes. Analysis of the functions of the differentially expressed genes revealed that each developmental stage had some unique types of expressed genes that are characteristic of the physiology at that stage. This is the first genome-wide analysis of genes differentially expressed in different stages in a gall midge. The large dataset of up- and down-regulated genes in each stage of the insect shall be very useful for future research to elucidate mechanisms regulating insect development and other biological processes. PMID:27224654

  1. Genomic basis of ecological niche divergence among cryptic sister species of non-biting midges

    PubMed Central

    2013-01-01

    Background There is a lack of understanding the evolutionary forces driving niche segregation of closely related organisms. In addition, pinpointing the genes driving ecological divergence is a key goal in molecular ecology. Here, larval transcriptome sequences obtained by next-generation-sequencing are used to address these issues in a morphologically cryptic sister species pair of non-biting midges (Chironomus riparius and C. piger). Results More than eight thousand orthologous open reading frames were screened for interspecific divergence and intraspecific polymorphisms. Despite a small mean sequence divergence of 1.53% between the sister species, 25.1% of 18,115 observed amino acid substitutions were inferred by α statistics to be driven by positive selection. Applying McDonald-Kreitman tests to 715 alignments of gene orthologues identified eleven (1.5%) genes driven by positive selection. Conclusions Three candidate genes were identified as potentially responsible for the observed niche segregation concerning nitrite concentration, habitat temperature and water conductivity. Additionally, signs of positive selection in the hydrogen sulfide detoxification pathway were detected, providing a new plausible hypothesis for the species’ ecological differentiation. Finally, a divergently selected, nuclear encoded mitochondrial ribosomal protein may contribute to reproductive isolation due to cytonuclear coevolution. PMID:23758757

  2. Factors affecting methylmercury biomagnification by a widespread aquatic invertebrate predator, the phantom midge larvae Chaoborus.

    PubMed

    Le Jeune, Anne-Hélène; Bourdiol, Floriane; Aldamman, Lama; Perron, Tania; Amyot, Marc; Pinel-Alloul, Bernadette

    2012-06-01

    MeHg biomagnification by the phantom midge Chaoborus in relation to MeHg concentrations in their prey and its migratory behavior was investigated in two Canadian Precambrian Shield lakes. Three Chaoborus species with contrasted migratory behavior were collected in a fishless and a fish-inhabited lake. All species accumulated MeHg through their ontogenic development. In the lake inhabited by fish, all instars of Chaoborus punctipennis displayed a marked migratory behavior and were unable to biomagnify MeHg, whereas in the fishless lake, Chaoborus americanus and Chaoborus trivittatus biomagnified MeHg. Reduced biomagnification capacity of C. trivittatus, the coexisting species living with C. americanus, was also ascribed to a progressive vertical segregation with age. Growth dilution, amount and type of prey items or trophic position could not explain the different patterns of biomagnification. Our findings demonstrate that the most common invertebrate predator of temperate planktonic food webs can biomagnify mercury, contrarily to previous reports. PMID:22420993

  3. A Determination of Metallothionein in Larvae of Freshwater Midges (Chironomus riparius) Using Brdicka Reaction

    PubMed Central

    Fabrik, Ivo; Ruferova, Zuzana; Hilscherova, Klara; Adam, Vojtech; Trnkova, Libuse; Kizek, Rene

    2008-01-01

    Among wide spectrum of biomolecules induced by various stress factors low molecular mass protein called metallothionein (MT) is suitable for assessment of the heavy metal environmental pollution. The aim of this work was to determine the metallothionein and total thiols content in larvae of freshwater midges (Chironomus riparius) sampled from laboratory exposure to cadmium(II) ions and from field studies using differential pulse voltammetry Brdicka reaction. Unique electrochemical instrument, stationary electrochemical analyser Autolab coupled with autosampler, was utilized for the analysis of the samples. The detection limit for MT was evaluated as 5 nM. The larvae exposed to two doses (50 ng/g or 50 μg/g) of cadmium(II) ions for fifteen days under laboratory controlled conditions were at the end of the exposure killed, homogenized and analysed. MT content in control samples was 1.2 μM, in larvae exposed to 50 ng Cd/g it was 2.0 μM and in larvae exposed to 50 μg Cd/g 2.9 μM. Moreover at field study chironomid larvae as well as sediment samples have been collected from eight field sites with different levels of pollution by heavy. The metals content (chromium, nickel, copper, zinc, arsenic, molybdenum, cadmium, tin and lead) in the sediment and or MT content in the chironomid larvae were determined by inductively coupled plasma mass spectrometry or Brdicka reaction, respectively.

  4. A Staging Scheme for the Development of the Moth Midge Clogmia albipunctata

    PubMed Central

    Gavilán, Brenda; Jaeger, Johannes

    2014-01-01

    Model organisms, such as Drosophila melanogaster, allow us to address a wide range of biological questions with experimental rigour. However, studies in model species need to be complemented by comparative studies if we are to fully understand the functional properties and evolutionary history of developmental processes. The establishment of new model organisms is crucial for this purpose. One of the first essential steps to establish a species as an experimental model is to carefully describe its life cycle and development. The resulting staging scheme serves as a framework for molecular studies, and allows us to homologise developmental processes between species. In this paper, we have characterised the life cycle and development of an emerging non-drosophilid dipteran model system: the moth midge Clogmia albipunctata. In particular, we focus on early embryogenesis (cleavage and blastoderm cycles before gastrulation), on formation and retraction of extraembryonic tissues, and on formation of the germ line. Considering the large evolutionary distance between the two species (approximately 250 million years), we find that the development of C. albipunctata is remarkably conserved compared to D. melanogaster. On the other hand, we detect significant differences in morphology and timing affecting the development of extraembryonic tissues and the germ line. Moreover, C. albipunctata shows several heterochronic shifts, and lacks head involution and associated processes during late stages of development. PMID:24409296

  5. A staging scheme for the development of the moth midge Clogmia albipunctata.

    PubMed

    Jiménez-Guri, Eva; Wotton, Karl R; Gavilán, Brenda; Jaeger, Johannes

    2014-01-01

    Model organisms, such as Drosophila melanogaster, allow us to address a wide range of biological questions with experimental rigour. However, studies in model species need to be complemented by comparative studies if we are to fully understand the functional properties and evolutionary history of developmental processes. The establishment of new model organisms is crucial for this purpose. One of the first essential steps to establish a species as an experimental model is to carefully describe its life cycle and development. The resulting staging scheme serves as a framework for molecular studies, and allows us to homologise developmental processes between species. In this paper, we have characterised the life cycle and development of an emerging non-drosophilid dipteran model system: the moth midge Clogmia albipunctata. In particular, we focus on early embryogenesis (cleavage and blastoderm cycles before gastrulation), on formation and retraction of extraembryonic tissues, and on formation of the germ line. Considering the large evolutionary distance between the two species (approximately 250 million years), we find that the development of C. albipunctata is remarkably conserved compared to D. melanogaster. On the other hand, we detect significant differences in morphology and timing affecting the development of extraembryonic tissues and the germ line. Moreover, C. albipunctata shows several heterochronic shifts, and lacks head involution and associated processes during late stages of development. PMID:24409296

  6. Effects of acid-volatile sulfide on metal bioavailability and toxicity to midge (Chironomus tentans) larvae in black shale sediments.

    PubMed

    Ogendi, George M; Brumbaugh, William G; Hannigan, Robyn E; Farris, Jerry L

    2007-02-01

    Metal bioavailability and toxicity to aquatic organisms are greatly affected by variables such as pH, hardness, organic matter, and sediment acid-volatile sulfide (AVS). Sediment AVS, which reduces metal bioavailability and toxicity by binding and immobilizing metals as insoluble sulfides, has been studied intensely in recent years. Few studies, however, have determined the spatial variability of AVS and its interaction with simultaneously extracted metals (SEM) in sediments containing elevated concentrations of metals resulting from natural geochemical processes, such as weathering of black shales. We collected four sediment samples from each of four headwater bedrock streams in northcentral Arkansa (USA; three black shale-draining streams and one limestone-draining stream). We conducted 10-d acute whole-sediment toxicity tests using the midge Chironomus tentans and performed analyses for AVS, total metals, SEMs, and organic carbon. Most of the sediments from shale-draining streams had similar total metal and SEM concentrations but considerable differences in organic carbon and AVS. Zinc was the leading contributor to the SEM molar sum, averaging between 68 and 74%, whereas lead and cadmium contributed less than 3%. The AVS concentration was very low in all but two samples from one of the shale streams, and the sum of the SEM concentrations was in molar excess of AVS for all shale stream sediments. No significant differences in mean AVS concentrations between sediments collected from shale-draining or limestone-draining sites were noted (p > 0.05). Midge survival and growth in black shale-derived sediments were significantly less (p < 0.001) than that of limestone-derived sediments. On the whole, either SEM alone or SEM-AVS explained the total variation in midge survival and growth about equally well. However, survival and growth were significantly greater (p < 0.05) in the two sediment samples that contained measurable AVS compared with the two sediments from the

  7. Effects of acid-volatile sulfide on metal bioavailability and toxicity to midge (Chironomus tentans) larvae in black shale sediments

    USGS Publications Warehouse

    Ogendi, G.M.; Brumbaugh, W.G.; Hannigan, R.E.; Farris, J.L.

    2007-01-01

    Metal bioavailability and toxicity to aquatic organisms are greatly affected by variables such as pH, hardness, organic matter, and sediment acid-volatile sulfide (AVS). Sediment AVS, which reduces metal bioavailability and toxicity by binding and immobilizing metals as insoluble sulfides, has been studied intensely in recent years. Few studies, however, have determined the spatial variability of AVS and its interaction with simultaneously extracted metals (SEM) in sediments containing elevated concentrations of metals resulting from natural geochemical processes, such as weathering of black shales. We collected four sediment samples from each of four headwater bedrock streams in northcentral Arkansa (USA; three black shale-draining streams and one limestone-draining stream). We conducted 10-d acute whole-sediment toxicity tests using the midge Chironomus tentans and performed analyses for AVS, total metals, SEMs, and organic carbon. Most of the sediments from shale-draining streams had similar total metal and SEM concentrations but considerable differences in organic carbon and AVS. Zinc was the leading contributor to the SEM molar sum, averaging between 68 and 74%, whereas lead and cadmium contributed less than 3%. The AVS concentration was very low in all but two samples from one of the shale streams, and the sum of the SEM concentrations was in molar excess of AVS for all shale stream sediments. No significant differences in mean AVS concentrations between sediments collected from shale-draining or limestone-draining sites were noted (p > 0.05). Midge survival and growth in black shale-derived sediments were significantly less (p < 0.001) than that of limestone-derived sediments. On the whole, either SEM alone or SEM-AVS explained the total variation in midge survival and growth about equally well. However, survival and growth were significantly greater (p < 0.05) in the two sediment samples that contained measurable AVS compared with the two sediments from the

  8. Efficacy of aerial spray applications using fuselage booms on Air Force C-130H aircraft against mosquitoes and biting midges.

    PubMed

    Breidenbaugh, Mark S; Haagsma, Karl A; Wojcik, George M; De Szalay, Ferenc A

    2009-12-01

    The effectiveness of a novel fuselage boom configuration was tested with flat-fan nozzles on U.S. Air Force C-130H aircraft to create ultra-low volume sprays to control mosquitoes (Culicidae) and biting midges (Ceratopogonidae). The mortality of mosquitoes and biting midges in bioassay cages and natural populations, using the organophosphate adulticide, naled, was measured. Mosquitoes in bioassay cages had 100% mortality at 639 m downwind in all single-pass spray trials, and most trials had >90% mortality up to 1491 m downwind. Mosquito mortality was negatively correlated with distance from the spray release point (r2 = 0.38, P < 0.001). The volume median diam of droplets collected was 44 tm at 213 m and decreased to 11 microm at 2130 m downwind of the release point. Droplet density decreased from an average of 18.4 drops/cm2 at 213 m to 2 drops/cm2 at 2130 m. Droplet densities of 10-18 droplets/cm2 were recorded at sampling stations with high mosquito mortality rates (>90%). In wide-area operational applications, numbers of mosquitoes from natural populations 1 wk postspray were 83% (range 55%-95%), lower than prespray numbers (P < 0.05). Biting midge numbers were reduced by 86% (range 53%-97%) on average (P = 0.051) after 7 days. The results of these field trials indicate that the fuselage boom configuration on C-130H aircraft are an effective method to conduct large-scale aerial sprays during military operations and public health emergencies. PMID:20099594

  9. Biodiversity of Asian rice gall midge (Orseolia oryzae Wood Mason) from five countries examined by AFLP analysis.

    PubMed

    Katiyar, S K; Chandel, G; Tan, Y; Zhang, Y; Huang, B; Nugaliyadde, L; Fernando, K; Bentur, J S; Inthavong, S; Constantino, S; Bennett, J

    2000-04-01

    Amplified fragment length polymorphism (AFLP) analysis was used to assess the biodiversity of one of the most important dipteran pests of cereals, the Asian rice gall midge (Orseolia oryzae Wood Mason). Larvae and pupae were collected at 15 locations in five Asian countries and preserved in 95% ethanol for storage, shipment, and DNA extraction using cetyltrimethylammonium bromide (CTAB). Although only approximately 1 microg of DNA was extracted from a single pupa or larva, the use of several AFLP primers in various combinations meant that this amount of DNA was sufficient to allow many DNA fingerprints to be made per individual. Fingerprints were sufficiently reproducible, especially during selective amplification, to allow the genetic diversity within a field population to be characterized. Extraction of DNA from a pool of 20 insects yielded AFLP fingerprints in which variation among individuals was sacrificed in favor of detecting differences among populations. For each location, pooled DNA was amplified with three primer pairs. A total of 261 distinct AFLP bands were identified for the 45 fingerprints. Cluster analysis, performed by the unweighted pair-group method (UPGMA), separated the populations into two distinct groups. Group I included two populations from Guangdong province of southern China and one each from Laos and Imphal in northeastern India, while group II was comprised of eleven populations from elsewhere in India (Assam, Orissa, Madhya Pradesh, Andhra Pradesh, and Kerala) and from Nepal and Sri Lanka. AFLP analysis provided insight into the origins of gall midge biotypes. In 1992, the prevailing biotype in Imphal changed from Indian biotype 3 to a new biotype 3M. Our data show that biotype 3M belongs to group I and did not arise by a recent mutation from biotype 3, which belongs to group II. By contrast, Indian biotypes 2 and 4 are likely to have diverged through recent mutation and selection, as are Chinese biotypes 1 and 4. The almost

  10. New records of predaceous midges from the Middle East, with the description of two new species (Diptera: Ceratopogonidae).

    PubMed

    Dominiak, Patrycja; Alwin, Alicja; Giłka, Wojciech

    2014-01-01

    Two new distinctive species of predaceous biting midges of the tribe Ceratopogonini are described and illustrated from the Middle East. Brachypogon freidbergi sp. nov., with a unique Y-shaped gonostylus, is recorded from Israel. We also provide the first records of Brachypogon vitiosus (Winnertz) and B. aethiopicus (Clastrier, Rioux & Descous) from this country, and a key to the adult males of the genus Brachypogon Kieffer from the Middle East. Ceratopogon azari sp. nov., described from Lebanon, shows a distinctive structure of the male genital apparatus, and is the southernmost species of that genus in the Western Palaearctic. PMID:24872285

  11. Why oviposit there? Fitness consequences of a gall midge choosing the plant's youngest leaf.

    PubMed

    Ganehiarachchi, G A S M; Anderson, Kirk M; Harmon, Jason; Harris, Marion O

    2013-02-01

    For animals that lay eggs, a longstanding question is, why do females choose particular oviposition sites? For insects that lay eggs on plants there are three hypotheses: maximizing suitable habitat for juveniles, maximizing female lifespan, and maximizing egg survival. We investigated the function of the oviposition-site choice behavior of a gall midge, the Hessian fly, Mayetiola destructor (Say). In spite of living less than a day and having hundreds of eggs, the ovipositing female is choosy about the placement of eggs. Choosiness makes sense. The tiny gall-making neonate larva has limited movement and strict requirements for colonization. We examined whether offspring benefit from the Hessian fly female's preference for the plant's youngest leaf. To do this we restricted the female's access to the first, second, or third leaf of a seedling (wheat Triticum aestivum L.) plant. Being placed on older leaves did not impact egg survival or larval survival during migration to attack sites at the base of the plant, but did have negative impacts on egg-to-adult survival (reduced by 48%) and reproductive potential (reduced by 30-45%). These negative impacts appear to come from larvae having to search harder to find the limited number of reactive plant cells that can be reprogrammed to form the gall nutritive tissue. We propose that the ability of larvae to find these reactive cells in spite of being placed on an older leaf is important because it creates leeway for female behavior to evolve in the face of other selection pressures, e.g., attack by egg parasitoids. PMID:23339793

  12. Diversity of Non-Biting Midge Larvae Assemblages in the Jacuí River Basin, Brazil

    PubMed Central

    Floss, Elzira Cecília Serafini; Kotzian, Carla Bender; Spies, Márcia Regina; Secretti, Elisangela

    2012-01-01

    The richness and composition of a mountain-river chironomid larvae assemblage in the Jacuí River basin, Brazil were studied, and compared with other riverine non-biting midge larvae assemblages previously studied in the country. Additionally, the influence of some regional-scale environmental characteristics on the spatial distribution of these assemblages was tested. The specimens were collected at 12 sites in the middle course of the Jacuí River basin (in the state of Rio Grande do Sul) between April 2000 and May 2002. Around 100 taxa were recorded. The dominant taxa belonged to the genera Rheotanytarsus, Cricotopus, Polypedilum, and Pseudochironomus. Twenty-two rare taxa were found, representing 22% of the total of taxa inventoried. Fourteen genera (Aedokritus, Axarus, Endotribelos, Kiefferulus, Manoa, Oukuriella, Phaenopsectra, Stenochironomus, Xenochironomus, Xestochironomus, Cardiocladius, Metriocnemus, Paracladius, and Rheocricotopus) represent new occurrences in Rio Grande do Sul. The similarity analysis of the chironomid larvae assemblages inventoried in 32 regions of Brazil indicated five groups with similarity higher than 50%. The groups, when the effects of spatial autocorrelation were removed, displayed a weak positive correlation between the assemblage composition and the aquatic system or hydraulic conditions and the hydrographic basin, and a weak negative correlation in relation to the biome. The altitude showed no correlation with the composition of the assemblage. The relatively high richness of the region surveyed in relation to other Brazilian regions corroborates some tendencies already noted in other parts of the world, such as: i) lotic systems may constitute an exception to the rule that diversity is greater in tropical regions, ii) regions of transitional relief may contain the greatest richness of Chironomidae, and iii) in rivers, the group might have its spatial distribution influenced to a greater extent by local environmental

  13. Pre-adapted to the maritime Antarctic?--rapid cold hardening of the midge, Eretmoptera murphyi.

    PubMed

    Everatt, M J; Worland, M R; Bale, J S; Convey, P; Hayward, S A L

    2012-08-01

    During the 1960s, the midge, Eretmoptera murphyi, was transferred from sub-Antarctic South Georgia (55°S 37°W) where it is endemic to a single location on maritime Antarctic Signy Island (60°S 45°W). Its distribution has since expanded considerably, suggesting that it is pre-adapted to the more severe conditions further south. To test one aspect of the level of its pre-adaptation, the rapid cold hardening (RCH) response in this species was investigated. When juvenile (L1-L2) and mature (L3-L4) larvae of E. murphyi were directly exposed to progressively lower temperatures for 8h, they exhibited Discriminating Temperatures (DTemp, temperature at which there is 10-20% survival of exposed individuals) of -11.5 and -12.5°C, respectively. The mean SCP was above -7.5°C in both larval groups, confirming the finding of previous studies that this species is freeze-tolerant. Following gradual cooling (0.2°Cmin(-1)), survival was significantly greater at the DTemp in both larval groups. The response was strong, lowering the lower lethal temperature (LLT) by up to 6.5°C and maintaining survival above 80% for at least 22h at the DTemp. RCH was also exhibited during the cooling phase of an ecologically relevant thermoperiodic cycle (+4°C to -3°C). Mechanistically, the response did not affect freezing, with no alteration in the supercooling point (SCP) found following gradual cooling, and was not induced while the organism was in a frozen state. These results are discussed in light of E. murphyi's pre-adaptation to conditions on Signy Island and its potential to colonize regions further south in the maritime Antarctic. PMID:22684111

  14. Bringing gay and lesbian activism to the White House: Midge Costanza and the National Gay Task Force Meeting.

    PubMed

    Mattingly, Doreen J; Boyd, Ashley

    2013-01-01

    In March 1977, President Carter's Assistant Margaret "Midge" Costanza made history by meeting with representatives from the National Gay Task Force (NGTF) to hear their grievances about discriminatory federal policies. The effects of the meeting were many, including changes in policies of the Bureau of Prisons and the Public Health Service. It also initiated policy discussions that would continue for decades and contributed to the incorporation of gay rights within the Democratic Party. Midge Costanza was fundamental to the process. It was her decision to hold the meeting and to advocate on behalf of the NGTF, and she bore many of the meeting's political costs. In this article we make use of Costanza's own papers and multiple interviews with her to closely analyze Costanza's role in the historic meeting. In addition to adding detail to its politics and policy impacts of the meeting, we also look at her complex motivations for holding such a controversial meeting. Costanza maintained until her death in 2010 that she was motivated by her feminism and overall commitment to social justice, rather than her own identity or experiences. PMID:23855947

  15. Deep sequencing and genome-wide analysis reveals the expansion of MicroRNA genes in the gall midge Mayetiola destructor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    MicroRNAs (miRNAs) are small noncoding RNAs that play critical roles in regulating gene expression post transcription. Gall midges are a large group of insects that are of economical importance and also possess fascinating biological traits. In this study, we systematically analyzed miRNAs from th...

  16. Functional responses and prey-stage preferences of a predatory gall midge and two predacious mites wtih twospotted spider mites, Tetranychus urticae as host

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The twospotted spider mite, Tetranychus urticae (Acari: Tetranychidae), is an important pest of vegetables and other crops. This study was conducted to evaluate and compare the potential role of three commercially available predators, predatory gall midge, Feltiella acarisuga (Vallot) (Diptera: Ceci...

  17. Full Genome Characterization of the Culicoides-Borne Marsupial Orbiviruses: Wallal Virus, Mudjinbarry Virus and Warrego Viruses

    PubMed Central

    Belaganahalli, Manjunatha N.; Maan, Sushila; Maan, Narender S.; Pritchard, Ian; Kirkland, Peter D.; Brownlie, Joe; Attoui, Houssam; Mertens, Peter P. C.

    2014-01-01

    Viruses belonging to the species Wallal virus and Warrego virus of the genus Orbivirus were identified as causative agents of blindness in marsupials in Australia during 1994/5. Recent comparisons of nucleotide (nt) and amino acid (aa) sequences have provided a basis for the grouping and classification of orbivirus isolates. However, full-genome sequence data are not available for representatives of all Orbivirus species. We report full-genome sequence data for three additional orbiviruses: Wallal virus (WALV); Mudjinabarry virus (MUDV) and Warrego virus (WARV). Comparisons of conserved polymerase (Pol), sub-core-shell ‘T2’ and core-surface ‘T13’ proteins show that these viruses group with other Culicoides borne orbiviruses, clustering with Eubenangee virus (EUBV), another orbivirus infecting marsupials. WARV shares <70% aa identity in all three conserved proteins (Pol, T2 and T13) with other orbiviruses, consistent with its classification within a distinct Orbivirus species. Although WALV and MUDV share <72.86%/67.93% aa/nt identity with other orbiviruses in Pol, T2 and T13, they share >99%/90% aa/nt identities with each other (consistent with membership of the same virus species - Wallal virus). However, WALV and MUDV share <68% aa identity in their larger outer capsid protein VP2(OC1), consistent with membership of different serotypes within the species - WALV-1 and WALV-2 respectively. PMID:25299687

  18. Pyrosequencing Reveals the Predominance of Pseudomonadaceae in Gut Microbiome of a Gall Midge

    PubMed Central

    Bansal, Raman; Hulbert, Scot H.; Reese, John C.; Whitworth, Robert J.; Stuart, Jeffrey J.; Chen, Ming-Shun

    2014-01-01

    Gut microbes are known to play various roles in insects such as digestion of inaccessible nutrients, synthesis of deficient amino acids, and interaction with ecological environments, including host plants. Here, we analyzed the gut microbiome in Hessian fly, a serious pest of wheat. A total of 3,654 high quality sequences of the V3 hypervariable region of the 16S rRNA gene were obtained through 454-pyrosequencing. From these sequences, 311 operational taxonomic units (OTUs) were obtained at the ≥97% similarity cutoff. In the gut of 1st instar, otu01, a member of Pseudomonas, was predominant, representing 90.2% of total sequences. otu13, an unidentified genus in the Pseudomonadaceae family, represented 1.9% of total sequences. The remaining OTUs were each less than 1%. In the gut of the 2nd instar, otu01 and otu13 decreased to 85.5% and 1.5%, respectively. otu04, a member of Buttiauxella, represented 9.7% of total sequences. The remaining OTUs were each less than 1%. In the gut of the 3rd instar, otu01 and otu13 further decreased to 29.0% and 0%, respectively. otu06, otu08, and otu16, also three members of the Pseudomonadaceae family were 13.2%, 8.6%, and 2.3%, respectively. In addition, otu04 and otu14, two members of the Enterobacteriaceae family, were 4.7% and 2.5%; otu18 and otu20, two members of the Xanthomonadaceae family, were 1.3% and 1.2%, respectively; otu12, a member of Achromobacter, was 4.2%; otu19, a member of Undibacterium, was 1.4%; and otu9, otu10, and otu15, members of various families, were 6.1%, 6.3%, and 1.9%, respectively. The investigation into dynamics of Pseudomonas, the most abundant genera, revealed that its population level was at peak in freshly hatched or 1 day larvae as well as in later developmental stages, thus suggesting a prominent role for this bacterium in Hessian fly development and in its interaction with host plants. This study is the first comprehensive survey on bacteria associated with the gut of a gall midge, and

  19. A systematic analysis of the gap gene system in the moth midge Clogmia albipunctata.

    PubMed

    García-Solache, Mónica; Jaeger, Johannes; Akam, Michael

    2010-08-01

    The segmentation gene hierarchy of Drosophila melanogaster represents one of the best understood of the gene networks that generate pattern during embryogenesis. Some components of this network are ancient, while other parts of the network have evolved within the higher Diptera. To further understand the evolution of this gene network, we are studying the role of gap genes in a representative of a basally diverging dipteran lineage, the moth midge Clogmia albipunctata. We have isolated orthologues of all of the Drosophila trunk gap genes from Clogmia, and determined their domains of expression during the blastoderm stage of development, in relation to one another, and in relation to the expression of even-skipped (Calb-eve), a component of the pair-rule system that is directly regulated by the gap genes in Drosophila. We find that hunchback (Calb-hb), Krüppel (Calb-Kr), knirps (Calb-knl), giant (Calb-gt) and tailless (Calb-tll) are all expressed in patterns consistent with a gap segmentation role during blastoderm formation, but huckebein (Calb-hkb) is not. In the anterior half of the embryo, the relative positions of the gap gene expression domains in relation to one another, and in relation to the eve stripes, are rather well conserved. In the posterior half of the embryo, there are significant differences. Posteriorly, Calb-gt is expressed only transiently and very weakly, in a domain that overlaps entirely with that of Calb-knl. At late blastoderm stages, none of the candidate genes we have tested is expressed in the region between the posterior Calb-knl domain and Calb-tll. It is likely that the regulation of Calb-eve expression in this posterior region depends on combinations of gap gene factors that differ from those utilised for the same stripes in Drosophila. Both the gap and the pair-rule patterns of gene expression are dynamic in Clogmia, as they are in Drosophila, shifting anteriorly as blastoderm development proceeds. PMID:20433825

  20. An equal sex ratio followed by differential sex mortality causes overestimation of females in gall midges: no evidence for sex ratio regulation.

    PubMed

    Tabadkani, Seyed Mohammad; Ashouri, Ahmad; Qolizadeh, Majid

    2012-06-01

    Monogeny, the production of unisexual broods by individual females, has been recognized for nearly 80 years. The genetic nature of gall midges' sex determination predicts an equal numbers of male-producing and female-producing females in the populations such that the overall sex ratio is expected to be nearly 1:1. However, observations of some strictly monogenous populations with biased sex ratio, mainly toward females, have raised the question of whether gall midges are able to adjust their offspring sex ratio in response to changes in environmental conditions, and some authors have even considered sex ratio regulation as a strong force in the course of the evolution of monogeny. In this paper, first, by studying the sex ratio variations of the predatory gall midge, Aphidoletes aphidimyza within a generation, we showed that adult males emerge up to 1 day earlier and have shorter life span than females (less than 4 days and up to 6 days, respectively). Although, the sex ratio of A. aphidimyza at the time of emergence was nearly 1:1 (52.41% males), a simple population simulation indicated that the differential mortality of sexes can lead to a female-biased sex ratio estimation (57.88% females) under random sampling in the natural environments. Our results imply that the primary sex ratio of monogenous gall midges is nearly 1:1 and that the arrhenogenic/thelygenic gall midges are not able to alter the number of their male/female progenies in response to changes in environmental conditions. PMID:22643882

  1. An equal sex ratio followed by differential sex mortality causes overestimation of females in gall midges: no evidence for sex ratio regulation

    NASA Astrophysics Data System (ADS)

    Tabadkani, Seyed Mohammad; Ashouri, Ahmad; Qolizadeh, Majid

    2012-06-01

    Monogeny, the production of unisexual broods by individual females, has been recognized for nearly 80 years. The genetic nature of gall midges' sex determination predicts an equal numbers of male-producing and female-producing females in the populations such that the overall sex ratio is expected to be nearly 1:1. However, observations of some strictly monogenous populations with biased sex ratio, mainly toward females, have raised the question of whether gall midges are able to adjust their offspring sex ratio in response to changes in environmental conditions, and some authors have even considered sex ratio regulation as a strong force in the course of the evolution of monogeny. In this paper, first, by studying the sex ratio variations of the predatory gall midge, Aphidoletes aphidimyza within a generation, we showed that adult males emerge up to 1 day earlier and have shorter life span than females (less than 4 days and up to 6 days, respectively). Although, the sex ratio of A. aphidimyza at the time of emergence was nearly 1:1 (52.41 % males), a simple population simulation indicated that the differential mortality of sexes can lead to a female-biased sex ratio estimation (57.88 % females) under random sampling in the natural environments. Our results imply that the primary sex ratio of monogenous gall midges is nearly 1:1 and that the arrhenogenic/thelygenic gall midges are not able to alter the number of their male/female progenies in response to changes in environmental conditions.

  2. Detection of Israel turkey meningo-encephalitis virus from mosquito (Diptera: Culicidae) and Culicoides (Diptera: Ceratopogonidae) species and its survival in Culex pipiens and Phlebotomus papatasi (Diptera: Phlebotomidae).

    PubMed

    Braverman, Y; Davidson, I; Chizov-Ginzburg, A; Chastel, C

    2003-07-01

    Israel turkey meningo-encephalitis (ITME) virus was detected in pools of Ochlerotatus caspius Pallas and Culicoides imicola Kieffer trapped at a turkey run at Nir David during an outbreak in August 1995. Experimental membrane feeding on a blood ITME suspension showed that Culex pipiens L. became harbored virus for at least 14 d. When Phlebotomus papatasi Scopoli were fed on an infected turkey, they became infected and harbored the virus for at least 7 d. Because Phlebotomines are trapped frequently at turkey runs in Israel, they should be suspected as potential vectors of ITME. PMID:14680120

  3. Discovery and Evolution of Bunyavirids in Arctic Phantom Midges and Ancient Bunyavirid-Like Sequences in Insect Genomes

    PubMed Central

    Bruenn, Jeremy A.; Hay, John; Czechowski, Donna; Taylor, Derek J.

    2014-01-01

    ABSTRACT Bunyaviridae is a large family of RNA viruses chiefly comprised of vertebrate and plant pathogens. We discovered novel bunyavirids that are approximately equally divergent from each of the five known genera. We characterized novel genome sequences for two bunyavirids, namely, Kigluaik phantom virus (KIGV), from tundra-native phantom midges (Chaoborus), and Nome phantom virus (NOMV), from tundra-invading phantom midges, and demonstrated that these bunyavirid-like sequences belong to an infectious virus by passaging KIGV in mosquito cell culture, although the infection does not seem to be well sustained beyond a few passages. Virus and host gene sequences from individuals collected on opposite ends of North America, a region spanning 4,000 km, support a long-term, vertically transmitted infection of KIGV in Chaoborus trivittatus. KIGV-like sequences ranging from single genes to full genomes are present in transcriptomes and genomes of insects belonging to six taxonomic orders, suggesting an ancient association of this clade with insect hosts. In Drosophila, endogenous virus genes have been coopted, forming an orthologous tandem gene family that has been maintained by selection during the radiation of the host genus. Our findings indicate that bunyavirid-host interactions in nonbloodsucking arthropods have been much more extensive than previously thought. IMPORTANCE Very little is known about the viral diversity in polar freshwater ponds, and perhaps less is known about the effects that climate-induced habitat changes in these regions will have on virus-host interactions in the coming years. Our results show that at the tundra-boreal boundary, a hidden viral landscape is being altered as infected boreal phantom midges colonize tundra ponds. Likewise, relatively little is known of the deeper evolutionary history of bunyavirids that has led to the stark lifestyle contrasts between some genera. The discovery of this novel bunyavirid group suggests that ancient

  4. Five new species and new records of biting midges of the genus Dasyhelea Kieffer from the Near East (Diptera: Ceratopogonidae).

    PubMed

    Dominiak, Patrycja; Alwin, Alicja

    2013-01-01

    As a result of the entomological surveys in the Near East, seventeen species of biting midges of the genus Dasyhelea Kieffer are reported. Five new species are described and illustrated from adult males: D. (Dicryptoscena) antonii sp. nov., D. (Pseudoculicoides) avia sp. nov., D. (Ps.) libanensis sp. nov., D. (Ps.) nauta sp. nov. and D. (Ps.) sandrageorgei sp. nov. Among the remaining species, four are recorded for the first time from this region. Furthermore, new country records for Iran (1 sp.), Israel (2 spp.), Lebanon (9 spp.) and Yemen (1 sp.) are given. Four species described by Kieffer in 1918, namely D. distalis, D. flaviscapula, D. scutellaris and D. trifasciata, are treated as doubtful names (nomina dubia) and excluded from the Turkish fauna. In addition, an updated checklist of Dasyhelea of the Near East is presented. Dasyhelea labinoda Mazumdar & Chaudhuri, 2009 is proposed as a new junior synonym of D. deemingi Boorman & Harten, 2002. New synonymy. PMID:25250442

  5. A Simulation Approach to Assessing Sampling Strategies for Insect Pests: An Example with the Balsam Gall Midge

    PubMed Central

    Carleton, R. Drew; Heard, Stephen B.; Silk, Peter J.

    2013-01-01

    Estimation of pest density is a basic requirement for integrated pest management in agriculture and forestry, and efficiency in density estimation is a common goal. Sequential sampling techniques promise efficient sampling, but their application can involve cumbersome mathematics and/or intensive warm-up sampling when pests have complex within- or between-site distributions. We provide tools for assessing the efficiency of sequential sampling and of alternative, simpler sampling plans, using computer simulation with “pre-sampling” data. We illustrate our approach using data for balsam gall midge (Paradiplosis tumifex) attack in Christmas tree farms. Paradiplosis tumifex proved recalcitrant to sequential sampling techniques. Midge distributions could not be fit by a common negative binomial distribution across sites. Local parameterization, using warm-up samples to estimate the clumping parameter k for each site, performed poorly: k estimates were unreliable even for samples of n∼100 trees. These methods were further confounded by significant within-site spatial autocorrelation. Much simpler sampling schemes, involving random or belt-transect sampling to preset sample sizes, were effective and efficient for P. tumifex. Sampling via belt transects (through the longest dimension of a stand) was the most efficient, with sample means converging on true mean density for sample sizes of n∼25–40 trees. Pre-sampling and simulation techniques provide a simple method for assessing sampling strategies for estimating insect infestation. We suspect that many pests will resemble P. tumifex in challenging the assumptions of sequential sampling methods. Our software will allow practitioners to optimize sampling strategies before they are brought to real-world applications, while potentially avoiding the need for the cumbersome calculations required for sequential sampling methods. PMID:24376556

  6. Thermal stress induces HSP70 proteins synthesis in larvae of the cold stream non-biting midge Diamesa cinerella Meigen.

    PubMed

    Lencioni, Valeria; Bernabò, Paola; Cesari, Michele; Rebecchi, Lorena; Cesari, Michele

    2013-05-01

    Laboratory experiments on the cold stenothermal midge Diamesa cinerella (Diptera, Chironomidae) were performed to study the relationship between increasing temperature and heat shock proteins (HSP70) expression at translational level (Western blotting). Thermotolerance of IV instar larvae collected in nature at 1.5-4.3°C during seasons was analyzed through short-term (1 h at ten different temperatures from 26°C to 35°C) and long-term (1-14 h at 26°C and 1-4 h at 32°C) heat shocks. A high thermotolerance was detected (LT50=30.9-32.8°C and LT100=34.0-37.8°C). However, survival decreased consistently with increasing exposure time, especially at higher temperature (LTime50=7.64 h at 26°C and LTime50=1.73 h at 32°C). The relationship between such heat resistance and HSP70 expression appeared evident because a relationship between HSP70 level and larval survival rate was generally found. A heat shock response (HSR) was consistent only in the summer larvae. The absence of HSR in the other populations coupled with even higher amounts of HSP70 than in summer, led us to hypothesize that other macromolecules and other adaptive mechanisms, apart from biochemical ones, are involved in the response of D. cinerella larvae to high temperature. Altogether these results stressed how in this midge the HSP70 protein family confers resistance against cold, being detected under natural conditions in control larvae collected in all seasons, but also against warm under experimental heat shocks. These results give new insights into possible responses to climate changes in freshwater insects within the context of global warming. PMID:23404797

  7. Osmoregulation and salinity tolerance in the Antarctic midge, Belgica antarctica: seawater exposure confers enhanced tolerance to freezing and dehydration.

    PubMed

    Elnitsky, Michael A; Benoit, Joshua B; Lopez-Martinez, Giancarlo; Denlinger, David L; Lee, Richard E

    2009-09-01

    Summer storms along the Antarctic Peninsula can cause microhabitats of the terrestrial midge Belgica antarctica to become periodically inundated with seawater from tidal spray. As microhabitats dry, larvae may be exposed to increasing concentrations of seawater. Alternatively, as a result of melting snow or following rain, larvae may be immersed in freshwater for extended periods. The present study assessed the tolerance and physiological response of B. antarctica larvae to salinity exposure, and examined the effect of seawater acclimation on their subsequent tolerance of freezing, dehydration and heat shock. Midge larvae tolerated extended exposure to hyperosmotic seawater; nearly 50% of larvae survived a 10-day exposure to 1000 mOsm kg(-1) seawater and approximately 25% of larvae survived 6 days in 2000 mOsm kg(-1) seawater. Exposure to seawater drastically reduced larval body water content and increased hemolymph osmolality. By contrast, immersion in freshwater did not affect water content or hemolymph osmolality. Hyperosmotic seawater exposure, and the accompanying osmotic dehydration, resulted in a significant correlation between the rate of oxygen consumption and larval water content and induced the de novo synthesis and accumulation of several organic osmolytes. A 3-day exposure of larvae to hyperosmotic seawater increased freezing tolerance relative to freshwater-acclimated larvae. Even after rehydration, the freezing survival of larvae acclimated to seawater was greater than freshwater-acclimated larvae. Additionally, seawater exposure increased the subsequent tolerance of larvae to dehydration. Our results further illustrate the similarities between these related, yet distinct, forms of osmotic stress and add to the suite of physiological responses used by larvae to enhance survival in the harsh and unpredictable Antarctic environment. PMID:19684222

  8. A broad assessment of factors determining Culicoides imicola abundance: modelling the present and forecasting its future in climate change scenarios.

    PubMed

    Acevedo, Pelayo; Ruiz-Fons, Francisco; Estrada, Rosa; Márquez, Ana Luz; Miranda, Miguel Angel; Gortázar, Christian; Lucientes, Javier

    2010-01-01

    Bluetongue (BT) is still present in Europe and the introduction of new serotypes from endemic areas in the African continent is a possible threat. Culicoides imicola remains one of the most relevant BT vectors in Spain and research on the environmental determinants driving its life cycle is key to preventing and controlling BT. Our aim was to improve our understanding of the biotic and abiotic determinants of C. imicola by modelling its present abundance, studying the spatial pattern of predicted abundance in relation to BT outbreaks, and investigating how the predicted current distribution and abundance patterns might change under future (2011-2040) scenarios of climate change according to the Intergovernmental Panel on Climate Change. C. imicola abundance data from the bluetongue national surveillance programme were modelled with spatial, topoclimatic, host and soil factors. The influence of these factors was further assessed by variation partitioning procedures. The predicted abundance of C. imicola was also projected to a future period. Variation partitioning demonstrated that the pure effect of host and topoclimate factors explained a high percentage (>80%) of the variation. The pure effect of soil followed in importance in explaining the abundance of C. imicola. A close link was confirmed between C. imicola abundance and BT outbreaks. To the best of our knowledge, this study is the first to consider wild and domestic hosts in predictive modelling for an arthropod vector. The main findings regarding the near future show that there is no evidence to suggest that there will be an important increase in the distribution range of C. imicola; this contrasts with an expected increase in abundance in the areas where it is already present in mainland Spain. What may be expected regarding the future scenario for orbiviruses in mainland Spain, is that higher predicted C. imicola abundance may significantly change the rate of transmission of orbiviruses. PMID:21151914

  9. A Broad Assessment of Factors Determining Culicoides imicola Abundance: Modelling the Present and Forecasting Its Future in Climate Change Scenarios

    PubMed Central

    Acevedo, Pelayo; Ruiz-Fons, Francisco; Estrada, Rosa; Márquez, Ana Luz; Miranda, Miguel Angel; Gortázar, Christian; Lucientes, Javier

    2010-01-01

    Bluetongue (BT) is still present in Europe and the introduction of new serotypes from endemic areas in the African continent is a possible threat. Culicoides imicola remains one of the most relevant BT vectors in Spain and research on the environmental determinants driving its life cycle is key to preventing and controlling BT. Our aim was to improve our understanding of the biotic and abiotic determinants of C. imicola by modelling its present abundance, studying the spatial pattern of predicted abundance in relation to BT outbreaks, and investigating how the predicted current distribution and abundance patterns might change under future (2011–2040) scenarios of climate change according to the Intergovernmental Panel on Climate Change. C. imicola abundance data from the bluetongue national surveillance programme were modelled with spatial, topoclimatic, host and soil factors. The influence of these factors was further assessed by variation partitioning procedures. The predicted abundance of C. imicola was also projected to a future period. Variation partitioning demonstrated that the pure effect of host and topoclimate factors explained a high percentage (>80%) of the variation. The pure effect of soil followed in importance in explaining the abundance of C. imicola. A close link was confirmed between C. imicola abundance and BT outbreaks. To the best of our knowledge, this study is the first to consider wild and domestic hosts in predictive modelling for an arthropod vector. The main findings regarding the near future show that there is no evidence to suggest that there will be an important increase in the distribution range of C. imicola; this contrasts with an expected increase in abundance in the areas where it is already present in mainland Spain. What may be expected regarding the future scenario for orbiviruses in mainland Spain, is that higher predicted C. imicola abundance may significantly change the rate of transmission of orbiviruses. PMID:21151914

  10. Population Genetic Structure and Potential Incursion Pathways of the Bluetongue Virus Vector Culicoides brevitarsis (Diptera: Ceratopogonidae) in Australia

    PubMed Central

    Tay, W. T.; Kerr, P. J.; Jermiin, L. S.

    2016-01-01

    Culicoides brevitarsis is a vector of the bluetongue virus (BTV), which infects sheep and cattle. It is an invasive species in Australia with an assumed Asian/South East Asian origin. Using one mitochondrial marker (i.e., part of the cytochrome oxidase subunit I gene) and six nuclear markers, we inferred population genetic structure and possible incursion pathways for Australian C. brevitarsis. Nine mitochondrial haplotypes, with low nucleotide sequence diversity (0.0–0.7%) among these, were identified in a sample of 70 individuals from seven sites. Both sets of markers revealed a homogeneous population structure, albeit with evidence of isolation by distance and two genetically distinct clusters distributed along a north-to-south cline. No evidence of a cryptic species complex was found. The geographical distribution of the mitochondrial haplotypes is consistent with at least two incursion pathways into Australia since the arrival of suitable livestock hosts. By contrast, 15 mitochondrial haplotypes, with up to four times greater nucleotide sequence diversity (0.0–2.9%) among these, were identified in a sample of 16 individuals of the endemic C. marksi (sampled from a site in South Australia and another in New South Wales). A phylogenetic tree inferred using the mitochondrial marker revealed that the Australian and Japanese samples of C. brevitarsis are as evolutionarily different from one another as some of the other Australian species (e.g., C. marksi, C. henryi, C. pallidothorax) are. The phylogenetic tree placed four of the species endemic to Australia (C. pallidothorax, C. bundyensis, C. marksi, C. henryi) in a clade, with a fifth such species (C. bunrooensis) sharing a common ancestor with that clade and a clade comprising two Japanese species (C. verbosus, C. kibunensis). PMID:26771743

  11. Lactoferrin, a glycoprotein with immunomodulatory and mast cell stabilising properties, in skin of horses suffering from Culicoides hypersensitivity.

    PubMed

    Kolm, Gabriela; Knapp, Elzbieta; Wagner, Regina; Klein, Dieter

    2007-10-01

    Lactoferrin (LF), a glycogen of the transferrin family with anti-bacterial and immunomodulatory properties, is expressed in various secretions and tissues. Cutaneous LF serves as a mast cell stabilising compound, modulates T cell activity and is found during IgE-mediated late phase reactions at allergen challenged sites. Culicoides hypersensitivity (CHS) in horses is a common IgE-mediated allergic dermatitis, characterised by an early and late phase cutaneous reaction upon allergen challenge. The aim of the study presented here was to examine whether LF mRNA expression in skin biopsies from horses affected by CHS prior to and 4h following intradermal challenge with a commercial C. nubeculosus extract is modified in comparison to skin biopsies from non-affected horses. In order to obtain reliable data, real time PCR was performed and genes of interest were normalized using three different housekeeping genes, beta-actin, GAPDH, beta-2-microglobulin. In comparison to non-affected horses, higher variation in LF mRNA levels both prior to and post-intradermal challenge with C. nubeculosus extract was seen in horses affected by CHS. However, the statistical analysis demonstrated that LF mRNA expression was not significantly different between CHS affected and non-affected horses prior to intradermal challenge with C. nubeculosus extract. Intradermal injection of C. nubeculosus extract did not result in local upregulation of LF mRNA at 4h post-injection. LF mRNA expression was therefore not significantly different pre- or post-intradermal challenge with C. nubeculosus extract in either group. Our data indicate that clinically normal skin of horses affected by CHS is not characterized by modified maintenance levels of LF mRNA. In contrast to human skin allergen challenged sites, LF mRNA levels in horses affected by CHS are not significantly different to that of control sites at 4h post-injection of C. nubeculosus extract. PMID:17222435

  12. From broadscale patterns to fine-scale processes: habitat structure influences genetic differentiation in the pitcher plant midge across multiple spatial scales.

    PubMed

    Rasic, Gordana; Keyghobadi, Nusha

    2012-01-01

    The spatial scale at which samples are collected and analysed influences the inferences that can be drawn from landscape genetic studies. We examined genetic structure and its landscape correlates in the pitcher plant midge, Metriocnemus knabi, an inhabitant of the purple pitcher plant, Sarracenia purpurea, across several spatial scales that are naturally delimited by the midge's habitat (leaf, plant, cluster of plants, bog and system of bogs). We analysed 11 microsatellite loci in 710 M. knabi larvae from two systems of bogs in Algonquin Provincial Park (Canada) and tested the hypotheses that variables related to habitat structure are associated with genetic differentiation in this midge. Up to 54% of variation in individual-based genetic distances at several scales was explained by broadscale landscape variables of bog size, pitcher plant density within bogs and connectivity of pitcher plant clusters. Our results indicate that oviposition behaviour of females at fine scales, as inferred from the spatial locations of full-sib larvae, and spatially limited gene flow at broad scales represent the important processes underlying observed genetic patterns in M. knabi. Broadscale landscape features (bog size and plant density) appear to influence oviposition behaviour of midges, which in turn influences the patterns of genetic differentiation observed at both fine and broad scales. Thus, we inferred linkages among genetic patterns, landscape patterns and ecological processes across spatial scales in M. knabi. Our results reinforce the value of exploring such links simultaneously across multiple spatial scales and landscapes when investigating genetic diversity within a species. PMID:21929541

  13. Pheromone-based action thresholds for control of the swede midge, Contarinia nasturtii (Diptera: Cecidomyiidae), and residual insecticide efficacy in cole crops.

    PubMed

    Hallett, Rebecca H; Sears, Mark K

    2013-02-01

    The swede midge, Contarinia nasturtii (Kieffer), is an invasive gall midge causing economic damage to cole crops (Brassica oleracea L.) and other crucifers in eastern Canada and United States. An effective decision-making tool for timing insecticide applications is a critical part of an integrated pest management program against C. nasturtii. Experiments were undertaken over 2 yr and at three locations in southern Ontario to develop pheromone-based action thresholds for C. nasturtii in cabbage and broccoli. An economic comparison between action threshold and calendar insecticide regimes was undertaken. The threshold approach was both economically viable and successful at minimizing swede midge damage for cabbage, and an action threshold of five males per trap per day with a minimum 7 d retreatment interval successfully reduced damage to acceptable levels. However, this approach was not successful with broccoli, which, unlike cabbage, is susceptible to damage by C. nasturtii through all plant stages, including heading. Acetamiprid and lambda-cyhalothrin both demonstrated approximately 7 d residual activity against C. nasturtii. Registration labels for both insecticides specify a minimum 7 d retreatment interval, which is supported by residual efficacy results. More effective insecticidal products may have longer residual efficacy and improve efficacy of the action threshold approach for broccoli and cabbage. PMID:23448040

  14. The 8200 cal yr BP cooling event in eastern North America and the utility of midge analysis for Holocene temperature reconstructions

    NASA Astrophysics Data System (ADS)

    Kurek, Joshua; Cwynar, Les C.; Spear, Ray W.

    2004-03-01

    Between about 8400 and 8000 cal yr BP two sites from the White Mountains of eastern North America record loss-on-ignition (LOI) reductions in the organic content of lake sediment. At Speck Pond LOI values reach a near-Holocene minimum of 35% whereas at Surplus Pond LOI values are maintained near 35% for about 100 cal yr. We interpret this change in LOI as a response to the 8200 cal yr BP cooling event known to occur throughout the circum-North Atlantic region. Detailed midge (including Chironomidae, Chaoboridae, and Ceratopogonidae) analyses were used to measure changes in summer surface-water temperatures from about 8800 to 8000 cal yr BP at both sites. Midge-inferred temperatures are highly variable at Speck Pond (ranging from 12.2°C to 16.7°C) whereas a "no-analogue" situation persists at Surplus Pond with inferred temperatures near 30°C. These results bring into question the usefulness of midges as a climate proxy to infer relatively brief, small-magnitude Holocene climatic events such as the 8200 cal yr BP cooling event.

  15. Changing the content of phenolic compounds as the response of blackcurrant (Ribes nigrum L.) leaves after blackcurrant leaf midge (Dasineura tetensi Rübs.) infestation.

    PubMed

    Piotrowski, Wojciech; Oszmiański, Jan; Wojdyło, Aneta; Łabanowska, Barbara H

    2016-09-01

    Blackcurrant leaf midge (Dasineura tetensi) is one of the most common pests of blackcurrant (Ribes nigrum). The aim of this study was to investigate changes in the content of phenolic compounds in the leaves damaged by the larvae of this pest. Additionally, susceptibility of different blackcurrant cultivars to the midge attack was investigated. Qualitative and quantitative analyses of control and pest-infested blackcurrant leaves were performed using LC-PDA-QTOF/MS and UPLC-PDA-FL systems. A total of 39 types of phenolic compounds were identified in blackcurrant leaf extracts and they included 3 flavan-3-ols, 14 hydroxycinnamic acid derivatives, and 22 flavonols. Feeding of blackcurrant leaf midge on blackcurrant leaves lowered the content of leaf polyphenolic compounds. The greatest differences in polyphenolics between control and infected leaves were observed in 'Ruben', 'Fariegh', 'Foxendown', 'Ores', 'Ben Hope', 'Ben Connan' and 'Tisel' cultivars that were probably highly susceptible to the pest attack. In the other cultivars: 'Ben Finlay', 'Polares', 'Tiben', and 'Gofert' the differences in phenolics content were less pronounced, so they were probably less susceptible to D. tetensi attack. Plant polyphenolic compounds was strongly involved in pathogen-plant interaction, and their accumulation significantly decreased as a result of the pathogen attack. PMID:27161581

  16. Host and Potential Vector Susceptibility to an Emerging Orbivirus in the United States: Epizootic Hemorrhagic Disease Virus Serotype 6.

    PubMed

    Ruder, M G; Stallknecht, D E; Allison, A B; Mead, D G; Carter, D L; Howerth, E W

    2016-05-01

    Epizootic hemorrhagic disease viruses (EHDVs) are orbiviruses transmitted byCulicoidesbiting midges to domestic and wild ruminants. EHDV-1 and EHDV-2 are endemic in the United States, where epizootic hemorrhagic disease is the most significant viral disease of white-tailed deer (WTD;Odocoileus virginianus) and reports of epizootic hemorrhagic disease in cattle are increasing. In 2006, a reassortant EHDV-6 was isolated from dead WTD in Indiana and has been detected each subsequent year over a wide geographic region. Since EHDV-6 is not a historically endemic serotype in the United States, it is important to understand infection outcome in potential hosts. Specifically, we aimed to evaluate the pathogenicity of the virus in 2 primary US ruminant hosts (WTD and cattle) and the susceptibility of a confirmed US vector (Culicoides sonorensis). Five WTD and 4 cattle were inoculated with >10(6)TCID50EHDV-6 by intradermal and subcutaneous injection. All 5 WTD exhibited moderate to severe disease, and 3 died. Viremia was first detected 3 to 5 days postinfection (dpi) with surviving animals seroconverting by 10 dpi. Two of 4 inoculated cattle had detectable viremia, 5 to 10 dpi and 7 to 24 dpi, respectively. No clinical, hematologic, or pathologic abnormalities were observed. Antibodies were detected by 10 dpi in 3 of 4 cows.C. sonorensiswere fed on WTD blood spiked with EHDV-6 and held for 4 to 14 days postfeeding at 25°C. From 4 to 14 days postfeeding, 19 of 171 midges were virus isolation positive and 6 of 171 had ≥10(2.7)TCID50EHDV-6. Although outcomes varied, these studies demonstrate the susceptibility of ruminant and vector hosts in the United States for this recently emerged EHDV serotype. PMID:26459518

  17. Laboratory evaluation of six algal species for larval nutritional suitability of the pestiferous midge Glyptotendipes paripes (Diptera: Chironomidae).

    PubMed

    Frouz, Jan; Ali, Arshad; Lobinske, Richard J

    2004-12-01

    Glyptotendipes paripes Edwards midge larval growth, development, survival, emerging adult size, and food digestibility when provided with six species of algae as food were studied in the laboratory. For the study, eggs from G. paripes adults maintained in the laboratory were reared to the adult stage at 30 degrees C for 60 d on pure culture of each algal species at densities of 0.4, 0.1, and 0.02 mg of algae (fresh weight) per milliliter, as a sole food source. All larvae reared on Microcystis sp., Botryoccocus braunii, and Scenedesmus quadricauda died before completing development. The only larvae to complete development to adult were those reared on 0.4 mg/ml Lyngbia cf. aeruginosa (44.0 d), Anabaena flos-aquae (29.7 d), and Chlorella keslerii (44.8 d). No significant differences in body size of the adults achieving complete development on the three algal species were found. Algal digestion, measured by comparing amounts of live and dead algal cells in remains of cultures used for feeding and in larval excrement, revealed that >95% of all L. cf. aeruginosa, A. flos-aquae, and Microcystis sp. cells were digested; for C. keslerii, 13% of cells were digested, whereas little or no digestion of B. braunii and S. quadricauda was observed. To evaluate the effects of algal species on larval growth, laboratory-reared (on artificial food) late third/early fourth instars of G. paripes were fed individual algal species, and 10 d later, body mass changes were recorded and compared with nonfed larvae. Body mass of larvae reared on L. cf. aeruginosa and A. flos-aquae significantly increased, whereas those provided Microcystis sp. and the nonfed larvae showed significant body mass reductions. Overall, B. braunii and S. quadricauda were not suitable as larval food, probably due to their low digestibility, and Microcystis sp. because of its toxicity. This study identifies some algae that do and others that do not support G. paripes larval growth. The information is useful in

  18. Purification and partial characterization of thermal hysteresis proteins from overwintering larvae of pine needle gall midge, Thecodiplosis japonensis (Diptera: cecidomiidae).

    PubMed

    Li, Y; Gong, H; Park, H Y

    2000-01-01

    The pine needle gall midge of Thecodiplosis japonensis is a serious forest pest and overwinters as a 3rd instar larva at soil surface in Korea. The time necessary for killing 50% of larvae at -15 degree C is 160 min. During overwintering period, T. japonensis larvae accumulate relatively high content of trehalose as the main cryoprotectant. In this paper, the proteinaceous cryoprotectants were identified. Two thermal hysteresis proteins (THP-1S and 2S) were purified from overwintering larvae by ethanol fractionation, trichloroacetic acid precipitation, ion-exchange chromatography (DEAE-Sephadex A-25) and gel permeation chromatography (Sephadex G-100). Their molecular weights are 34.9 and 37.8 kD respectively. T. japonensis THPs cannot be stained by periodic acid-Schiffs' reagent, suggesting no carbohydrate in them. The thermal hysteresis activity of THP-2 at the concentration of 50 mg/ml is 11.02 +/- 0.08 degree C (mean +/- SD, n=10), perhaps the highest active insect THP. It is the first report of purified T. japonensis THPs in Diptera. PMID:12148056

  19. Developing acute-to-chronic toxicity ratios for lead, cadmium, and zinc using rainbow trout, a mayfly, and a midge

    USGS Publications Warehouse

    Mebane, C.A.; Hennessy, D.P.; Dillon, F.S.

    2008-01-01

    In order to estimate acute-to-chronic toxicity ratios (ACRs) relevant to a coldwater stream community, we exposed rainbow trout (Oncorhynchus mykiss) to cadmium (Cd), lead (Pb), and zinc (Zn) in 96-h acute and 60+ day early-life stage (ELS) exposures. We also tested the acute and sublethal responses of a mayfly (Baetis tricaudatus) and a midge (Chironomus dilutus, formerly C. tentans) with Pb. We examine the statistical interpretation of test endpoints and the acute-to-chronic ratio concept. Increasing the number of control replicates by 2 to 3x decreased the minimum detectable differences by almost half. Pb ACR estimates mostly increased with increasing acute resistance of the organisms (rainbow trout ACRs

  20. Spatial and Temporal Distribution of Non-Biting Midge Larvae Assemblages in Streams in a Mountainous Region in Southern Brazil

    PubMed Central

    Floss, Elzira Cecília Serafini; Secretti, Elisangela; Kotzian, Carla Bender; Spies, Marcia Regina; Pires, Mateus Marques

    2013-01-01

    The spatial and temporal structure of non-biting midge (Diptera: Chironomidae) larvae assemblages and some environmental factors that affect their distribution were analyzed in a montane river and its tributaries in a temperate climate region of southernmost Brazil. In total, 69 taxa were recorded after four seasonal samplings (winter, spring, summer, and autumn). The dominant taxa were Rheotanytarsus sp. 1, Rheotanytarsus sp. 2, Cricotopus sp. 2, and Polypedilum (Polypedilum) sp., although dominance varied among the four sampling sites. The variations in dominance, abundance, and richness among the different sites were affected by environmental characteristics, such as the presence of marginal vegetation and a heterogeneous substratum, and also by human activities. Strictly environmental factors, such as altitude, and factors related to annual weather patterns, such as mean temperature and precipitation, influenced the spatial and temporal distribution of certain taxa and the structure of faunal assemblages. The influence of the riparian vegetation and riverbed heterogeneity on the composition, richness, and abundance of the chironomid larvae assemblages indicates that human activities, such as deforestation and the construction of dams, constitute a serious threat to the conservation of these insects and to the fauna that depends on them for food. PMID:24784953

  1. Prevalence and dynamics of the zoosporic pathogen Catenaria uncinata in a natural population of the midge Glyptotendipes lobiferus.

    PubMed

    Martin, W Wallace; Warren, Alyssa

    2016-09-01

    A qPCR assay specific for zoospores of Catenaria uncinata, a fungal parasite in eggs of the midge Glyptotendipes lobiferus, was developed and used in parallel with traditional microscopic methods in a season-long study of a C. uncinata/G. lobiferus association in a local pond. Twenty-six consecutive weekly collections of egg masses were screened with a microscope to obtain percentages of infection and mortality in organogenetic egg masses and weekly water samples were processed by absolute quantification using qPCR to obtain estimates of zoospore density. Overall, 36.0% of G. lobiferus egg masses were infected to varying degrees and 11.2% of eggs were killed by C. uncinata. Continuous infection of egg masses occurred during a 6-wk period in May-June and a 7-wk period in September-October. Infection by C. uncinata was absent during a 10-week interval between periods of infection. Abrupt declines in zoospore density occurred during both infection periods and occurred only when water temperatures met or exceeded the viability threshold for zoospores (⩾31.0°C). The episodic death of zoospores during weeks in which egg infection and mortality levels were continuous likely resulted from distribution of zoospores throughout the water column and a temperature gradient in which zoospores sampled near the surface were subjected to lethal temperatures while non-sampled zoospores at lower depths were provided low temperature sanctuary. The hiatus of infection during the 10-week interval was likely due to lethal temperatures throughout the water column as average water temperatures exceeded 31.0°C over the period. A positive correlation between weekly zoospore densities obtained from qPCR and levels of infection/mortality in egg masses obtained from counts with a microscope supports the use of the qPCR assay alone in future studies that can rapidly and accurately determine parasite presence, prevalence and geographical range. PMID:27418147

  2. Quantitative Temperature Reconstructions from Holocene and Late Glacial Lake Sediments in the Tropical Andes using Chironomidae (non-biting midges)

    NASA Astrophysics Data System (ADS)

    Matthews-Bird, F.; Gosling, W. D.; Brooks, S. J.; Montoya, E.; Coe, A. L.

    2014-12-01

    Chironomidae (non-biting midges) is a family of two-winged aquatic insects of the order Diptera. They are globally distributed and one of the most diverse families within aquatic ecosystems. The insects are stenotopic, and the rapid turnover of species and their ability to colonise quickly favourable habitats means chironomids are extremely sensitive to environmental change, notably temperature. Through the development of quantitative temperature inference models chironomids have become important palaeoecological tools. Proxies capable of generating independent estimates of past climate are crucial to disentangling climate signals and ecosystem response in the palaeoecological record. This project has developed the first modern environmental calibration data set in order to use chironomids from the Tropical Andes as quantitative climate proxies. Using surface sediments from c. 60 lakes from Bolivia, Peru and Ecuador we have developed an inference model capable of reconstructing temperatures, with a prediction error of 1-2°C, from fossil assemblages. Here we present the first Lateglacial and Holocene chironomid-inferred temperature reconstructions from two sites in the tropical Andes. The first record, from a high elevation (4153 m asl) lake in the Bolivian Andes, shows persistently cool temperatures for the past 15 kyr, punctuated by warm episodes in the early Holocene (9-10 kyr BP). The chironomid-inferred Holocene temperature trends from a lake sediment record on the eastern Andean flank of Ecuador (1248 m asl) spanning the last 5 millennia are synchronous with temperature changes in the NGRIP ice core record. The temperature estimates suggest along the eastern flank of the Andes, at lower latitudes (~1°S), climate closely resemble the well-established fluctuations of the Northern Hemisphere for this time period. Late-glacial climate fluctuations across South America are still disputed with some palaeoecological records suggesting evidence for Younger Dryas

  3. Evolution of early development in dipterans: reverse-engineering the gap gene network in the moth midge Clogmia albipunctata (Psychodidae).

    PubMed

    Crombach, Anton; García-Solache, Mónica A; Jaeger, Johannes

    2014-09-01

    Understanding the developmental and evolutionary dynamics of regulatory networks is essential if we are to explain the non-random distribution of phenotypes among the diversity of organismic forms. Here, we present a comparative analysis of one of the best understood developmental gene regulatory networks today: the gap gene network involved in early patterning of insect embryos. We use gene circuit models, which are fitted to quantitative spatio-temporal gene expression data for the four trunk gap genes hunchback (hb), Krüppel (Kr), giant (gt), and knirps (kni)/knirps-like (knl) in the moth midge Clogmia albipunctata, and compare them to equivalent reverse-engineered circuits from our reference species, the vinegar fly Drosophila melanogaster. In contrast to the single network structure we find for D. melanogaster, our models predict four alternative networks for C. albipunctata. These networks share a core structure, which includes the central regulatory feedback between hb and knl. Other interactions are only partially determined, as they differ between our four network structures. Nevertheless, our models make testable predictions and enable us to gain specific insights into gap gene regulation in C. albipunctata. They suggest a less central role for Kr in C. albipunctata than in D. melanogaster, and show that the mechanisms causing an anterior shift of gap domains over time are largely conserved between the two species, although shift dynamics differ. The set of C. albipunctata gene circuit models presented here will be used as the starting point for data-constrained in silico evolutionary simulations to study patterning transitions in the early development of dipteran species. PMID:24911671

  4. Relative sensitivity of an amphipod Hyalella azteca, a midge Chironomus dilutus, and a unionid mussel Lampsilis siliquoidea to a toxic sediment

    USGS Publications Warehouse

    Ingersoll, Christopher G.; Kunz, James L.; Hughes, James P.; Wang, Ning; Ireland, D. Scott; Mount, Dave R.; Hockett, Russ J; Valenti, Ted W

    2015-01-01

    The objective of the present study was to evaluate the relative sensitivity of test organisms in exposures to dilutions of a highly toxic sediment contaminated with metals and organic compounds. One dilution series was prepared using control sand (low total organic carbon [TOC; <0.1%, low binding capacity for contaminants]) and a second dilution series was prepared using control sediment from West Bearskin Lake, Minnesota, USA (high TOC [~10% TOC, higher binding capacity for contaminants]). Test organisms included an amphipod (Hyalella azteca; 10-d and 28-d exposures), a midge (Chironomus dilutus; 20-d and 48-d exposures started with <1-h-old larvae, and 13-d and 48-d exposures started with 7-d-old larvae), and a unionid mussel (Lampsilis siliquoidea; 28-d exposures). Relative species sensitivitydepended on the toxicity endpoint and the diluent. All 3 species were more sensitive in sand dilutions than in West Bearskin Lake sediment dilutions. The <1-h-old C. dilutus were more sensitive than 7-d-old C. dilutus, but replicate variability was high in exposures started with the younger midge larvae. Larval biomass and adult emergence endpoints of C. dilutus exhibited a similar sensitivity. Survival, weight, and biomass of H. azteca were more sensitive endpoints in 28-d exposures than in 10-d exposures. Weight and biomass of L. siliquoidea were sensitive endpoints in both sand and West Bearskin Lake sediment dilutions. Metals, ammonia, oil, and other organic contaminants may have contributed to the observed toxicity.

  5. Additive effects of predator cues and dimethoate on different levels of biological organisation in the non-biting midge Chironomus riparius.

    PubMed

    Van Praet, Nander; De Jonge, Maarten; Stoks, Robby; Bervoets, Lieven

    2014-10-01

    The combined effects of a pesticide and predation risk on sublethal endpoints in the midge Chironomus riparius were investigated using a combination of predator-release kairomones from common carp (Cyprinus carpio) and alarm substances from conspecifics together with the pesticide dimethoate. Midge larvae were exposed for 30 days to three sublethal dimethoate concentrations (0.01, 0.1 and 0.25 mg L(-1)) in the presence or absence of predator cues. Sublethal endpoints were analysed at different levels of biological organisation. Available energy reserves, enzyme biomarkers, feeding rate and life history endpoints were investigated. Three endpoints were significantly affected by the two highest dimethoate concentrations, i.e. AChE activity, age at emergence and emergence success, with a significant decrease in response after exposure to 0.25, 0.1 and 0.01 mg L(-1) dimethoate, respectively. Four sublethal endpoints were significantly affected by predator stress: Total protein content, GST activity and biomass decreased only in the presence of the predation risk, while AChE activity further decreased significantly in the presence of predation cues and effects on AChE of combined exposure were additive. From this study we can conclude that sublethal life history characteristics should be included in ecotoxicity testing as well as natural environmental stressors such as predator stress, which might act additively with pollutants on fitness related endpoints. PMID:25063887

  6. Morphological and Molecular Revision of the Genus Ozirhincus (Diptera: Cecidomyiidae)—Long-Snouted Seed-Feeding Gall Midges on Asteraceae

    PubMed Central

    Dorchin, Netta; Astrin, Jonas J.; Bodner, Levona; Harris, Keith M.

    2015-01-01

    The Palaearctic gall-midge genus Ozirhincus is unique among the Cecidomyiidae for its morphology and biology. Unlike most other phytophagous gall midges, species in this genus do not induce galls but develop inside achenes of Asteraceae plants. The heads of adults are characterized by an unusually elongate proboscis, the function of which is unclear. Despite a lot of attention from taxonomists in the 19th and early 20th century, a proper revision of the genus has been hindered by complex host associations, the loss of most relevant type material, and the lack of a thorough comparative study of all life stages. The present revision integrated morphological, molecular, and life-history data to clearly define species boundaries within Ozirhincus, and delimit host-plant ranges for each of them. A phylogenetic analysis based on the mitochondrial COI and 16S genes confirmed the validity of four distinct species but did not resolve the relationships among them. All species are oligophages, and some may occur together on the same host plant. Species with wider host-plant ranges have wider European and circum-Mediterranean distribution ranges, whereas species with narrower host ranges are limited to Europe and the Russian Far East. As part of the present work, O. hungaricus is reinstated from synonymy, O. tanaceti is synonymized under O. longicollis, neotypes are designated for O. longicollis and O. millefolii, and a lectotype is designated for O. anthemidis. PMID:26134526

  7. Relative sensitivity of an amphipod Hyalella azteca, a midge Chironomus dilutus, and a unionid mussel Lampsilis siliquoidea to a toxic sediment.

    PubMed

    Ingersoll, Chris G; Kunz, James L; Hughes, Jamie P; Wang, Ning; Ireland, D Scott; Mount, David R; Hockett, J Russell; Valenti, Theodore W

    2015-05-01

    The objective of the present study was to evaluate the relative sensitivity of test organisms in exposures to dilutions of a highly toxic sediment contaminated with metals and organic compounds. One dilution series was prepared using control sand (low total organic carbon [TOC; <0.1%, low binding capacity for contaminants]) and a second dilution series was prepared using control sediment from West Bearskin Lake, Minnesota, USA (high TOC [∼10% TOC, higher binding capacity for contaminants]). Test organisms included an amphipod (Hyalella azteca; 10-d and 28-d exposures), a midge (Chironomus dilutus; 20-d and 48-d exposures started with <1-h-old larvae, and 13-d and 48-d exposures started with 7-d-old larvae), and a unionid mussel (Lampsilis siliquoidea; 28-d exposures). Relative species sensitivity depended on the toxicity endpoint and the diluent. All 3 species were more sensitive in sand dilutions than in West Bearskin Lake sediment dilutions. The <1-h-old C. dilutus were more sensitive than 7-d-old C. dilutus, but replicate variability was high in exposures started with the younger midge larvae. Larval biomass and adult emergence endpoints of C. dilutus exhibited a similar sensitivity. Survival, weight, and biomass of H. azteca were more sensitive endpoints in 28-d exposures than in 10-d exposures. Weight and biomass of L. siliquoidea were sensitive endpoints in both sand and West Bearskin Lake sediment dilutions. Metals, ammonia, oil, and other organic contaminants may have contributed to the observed toxicity. PMID:25655578

  8. QTL Mapping in Three Rice Populations Uncovers Major Genomic Regions Associated with African Rice Gall Midge Resistance

    PubMed Central

    Semagn, Kassa; Sow, Mounirou; Nwilene, Francis; Kolade, Olufisayo; Bocco, Roland; Oyetunji, Olumoye; Mitchell-Olds, Thomas; Ndjiondjop, Marie-Noëlle

    2016-01-01

    African rice gall midge (AfRGM) is one of the most destructive pests of irrigated and lowland African ecologies. This study aimed to identify the quantitative trait loci (QTL) associated with AfRGM pest incidence and resistance in three independent bi-parental rice populations (ITA306xBW348-1, ITA306xTOG7106 and ITA306xTOS14519), and to conduct meta QTL (mQTL) analysis to explore whether any genomic regions are conserved across different genetic backgrounds. Composite interval mapping (CIM) conducted on the three populations independently uncovered a total of 28 QTLs associated with pest incidence (12) and pest severity (16). The number of QTLs per population associated with AfRGM resistance varied from three in the ITA306xBW348-1 population to eight in the ITA306xTOG7106 population. Each QTL individually explained 1.3 to 34.1% of the phenotypic variance. The major genomic region for AfRGM resistance had a LOD score and R2 of 60.0 and 34.1% respectively, and mapped at 111 cM on chromosome 4 (qAfrGM4) in the ITA306xTOS14519 population. The meta-analysis reduced the number of QTLs from 28 to 17 mQTLs, each explaining 1.3 to 24.5% of phenotypic variance, and narrowed the confidence intervals by 2.2 cM. There was only one minor effect mQTL on chromosome 1 that was common in the TOS14519 and TOG7106 genetic backgrounds; all other mQTLs were background specific. We are currently fine-mapping and validating the major effect genomic region on chromosome 4 (qAfRGM4). This is the first report in mapping the genomic regions associated with the AfRGM resistance, and will be highly useful for rice breeders. PMID:27508500

  9. QTL Mapping in Three Rice Populations Uncovers Major Genomic Regions Associated with African Rice Gall Midge Resistance.

    PubMed

    Yao, Nasser; Lee, Cheng-Ruei; Semagn, Kassa; Sow, Mounirou; Nwilene, Francis; Kolade, Olufisayo; Bocco, Roland; Oyetunji, Olumoye; Mitchell-Olds, Thomas; Ndjiondjop, Marie-Noëlle

    2016-01-01

    African rice gall midge (AfRGM) is one of the most destructive pests of irrigated and lowland African ecologies. This study aimed to identify the quantitative trait loci (QTL) associated with AfRGM pest incidence and resistance in three independent bi-parental rice populations (ITA306xBW348-1, ITA306xTOG7106 and ITA306xTOS14519), and to conduct meta QTL (mQTL) analysis to explore whether any genomic regions are conserved across different genetic backgrounds. Composite interval mapping (CIM) conducted on the three populations independently uncovered a total of 28 QTLs associated with pest incidence (12) and pest severity (16). The number of QTLs per population associated with AfRGM resistance varied from three in the ITA306xBW348-1 population to eight in the ITA306xTOG7106 population. Each QTL individually explained 1.3 to 34.1% of the phenotypic variance. The major genomic region for AfRGM resistance had a LOD score and R2 of 60.0 and 34.1% respectively, and mapped at 111 cM on chromosome 4 (qAfrGM4) in the ITA306xTOS14519 population. The meta-analysis reduced the number of QTLs from 28 to 17 mQTLs, each explaining 1.3 to 24.5% of phenotypic variance, and narrowed the confidence intervals by 2.2 cM. There was only one minor effect mQTL on chromosome 1 that was common in the TOS14519 and TOG7106 genetic backgrounds; all other mQTLs were background specific. We are currently fine-mapping and validating the major effect genomic region on chromosome 4 (qAfRGM4). This is the first report in mapping the genomic regions associated with the AfRGM resistance, and will be highly useful for rice breeders. PMID:27508500

  10. Record of two species of Culicoides (Diptera, Ceratopogonidae) new for Madagascar and molecular study showing the paraphylies of the subgenus Oecacta and the Schultzei group.

    PubMed

    Augot, D; Randrianambinintsoa, F J; Gasser, A; Depaquit, J

    2013-08-01

    Culicoides are vectors of diseases of Veterinary Medicine importance (bluetongue, African horse sickness, Schmallenberg virus) all over the world. In the present study, we report two species new for Madagascar: C. nevilli and C. enderleini. They belong to the Schultzei group which is sometimes classified in the subgenus Oecacta and sometimes in the subgenus Remmia, depending on authors. Consequently, we carried out a molecular cladistics of these groups based on cytochrome C oxidase subunit I mtDNA sequences. We processed the Malagasy specimens and some C. furens (the Oecacta type-species) caught in Florida and we analyzed their sequences and those available in Genbank: C. schultzei, C. oxystoma, C. festivipennis, C. brunnicans, C. kibunensis, C. truncorum and C. vexans. C. (Avaritia) imicola have been selected as an outgroup. The maximum parsimony analysis showed the paraphylies of the Schultzei group (=Remmia) and of the subgenus Oecacta if the first group is excluded from the latter. Our results underline the doubtful current classification and need to be validated by other molecular markers in the future. PMID:23893801

  11. Effects of ultra-low volume and thermal fog malathion, Scourge and naled applied against caged adult Culicoides furens and Culex quinquefasciatus in open and vegetated terrain.

    PubMed

    Linley, J R; Jordan, S

    1992-03-01

    The adulticidal effect of ULV and thermal fog malathion, Scourge and naled was tested at 2x label dosage (1.42, 0.22, 0.39 oz/acre, respectively) against caged Culicoides furens and Culex quinquefasciatus in open and vegetated (orange grove) terrain. Cages were at 122 cm elevation and positioned at 15.2, 45.7, 76.2, 106.7, 137.2 and 167.6 m from the line of insecticide release. Ultra-low volume applications of all 3 insecticides were markedly more effective than thermal fog under all conditions, especially in vegetated terrain. Of the 3 insecticides, malathion performed the poorest, especially against Cx. quinquefasciatus (in which there was some resistance) and particularly when applied as thermal fog. Scourge and naled were about equally effective. The best adulticide against C. furens was naled, which was clearly superior applied as ULV. It yielded 75% mortality out to 283 m in the open, and to 38 m in the presence of dense vegetation. PMID:1583493

  12. The Use of the Developmental Rate of the Aquatic Midge Chironomus riparius (Diptera, Chironomidae) in the Assessment of the Postsubmersion Interval.

    PubMed

    González Medina, Alejandro; Soriano Hernando, Óscar; Jiménez Ríos, Gilberto

    2015-05-01

    Nonbiting midges (Diptera, Chironomidae) are the most abundant members of the fauna associated with submerged carcasses, but their use in the medicolegal context is very restricted because of their complex ontogeny. In this case, the corpse of a woman was recovered in late spring from a river in Granada (Iberian Peninsula). It showed obvious signs of long permanence in the aquatic environment and, along with pulmonary and microscopical analyses, led to the conclusion that the cause of death was drowning. Several larvae-like specimens were sampled from the scalp and later identified by morphological external features as IV instar larvae of Chironomus riparius Meigen, 1804 (Diptera, Chironomidae). Sequencing of cytochrome oxidase subunit I was performed to confirm the identification. The knowledge of the biology of C. riparius at low temperatures was critical to assess a postsubmersion interval of 16-17 days. PMID:25613586

  13. Seroepidemiology of bluetongue in South Bengal

    PubMed Central

    Halder, Arkendu; Joardar, Siddhartha N.; Isore, Devi Prasad; Samanta, Indranil; Parui, Panchanan; Banerjee, Dhriti; Lodh, Chandan

    2016-01-01

    Aim: With the aim of revealing the epidemiological intricacies of bluetongue (BT) in the southern part of West Bengal state, the present study was undertaken to assess seroprevalence of BT along with identification of the vector of the disease, i.e., Culicoides midges available in the region in their breeding season with conducive environmental factors, if any. Materials and Methods: A total of 1509 (sheep-504, goat-1005) samples were collected from three different agroclimatic zones of South Bengal viz. new alluvial, red laterite and coastal saline. To detect anti-BT antibodies in the collected serum samples, indirect-enzyme-linked immunosorbent assay (i-ELISA) was performed. Culicoides midges were collected from those agro-climatic zones of South Bengal for species identification. The meteorological parameters, viz. temperature (maximum and minimum), rainfall and relative humidity of three agro-climatic zones of South Bengal were analyzed for the months of July to December during 2010-2013. Results: The overall seropositivity was 33.13% and 30.24% in sheep and goat, respectively as assessed by i-ELISA. In South Bengal, the predominant species of Culicoides found were Culicoides schultzei, Culicoides palpifer and Culicoides definitus. Conclusion: Since virus transmitting species of Culicoides midges could be detected in South Bengal, besides high seropositivity in ruminants, the possibility of circulating BT virus in South Bengal is quite imminent. PMID:27051176

  14. Cationic Lipid-Formulated DNA Vaccine against Hepatitis B Virus: Immunogenicity of MIDGE-Th1 Vectors Encoding Small and Large Surface Antigen in Comparison to a Licensed Protein Vaccine

    PubMed Central

    Endmann, Anne; Klünder, Katharina; Kapp, Kerstin; Riede, Oliver; Oswald, Detlef; Talman, Eduard G.; Schroff, Matthias; Kleuss, Christiane; Ruiters, Marcel H. J.; Juhls, Christiane

    2014-01-01

    Currently marketed vaccines against hepatitis B virus (HBV) based on the small (S) hepatitis B surface antigen (HBsAg) fail to induce a protective immune response in about 10% of vaccinees. DNA vaccination and the inclusion of PreS1 and PreS2 domains of HBsAg have been reported to represent feasible strategies to improve the efficacy of HBV vaccines. Here, we evaluated the immunogenicity of SAINT-18-formulated MIDGE-Th1 vectors encoding the S or the large (L) protein of HBsAg in mice and pigs. In both animal models, vectors encoding the secretion-competent S protein induced stronger humoral responses than vectors encoding the L protein, which was shown to be retained mainly intracellularly despite the presence of a heterologous secretion signal. In pigs, SAINT-18-formulated MIDGE-Th1 vectors encoding the S protein elicited an immune response of the same magnitude as the licensed protein vaccine Engerix-B, with S protein-specific antibody levels significantly higher than those considered protective in humans, and lasting for at least six months after the third immunization. Thus, our results provide not only the proof of concept for the SAINT-18-formulated MIDGE-Th1 vector approach but also confirm that with a cationic-lipid formulation, a DNA vaccine at a relatively low dose can elicit an immune response similar to a human dose of an aluminum hydroxide-adjuvanted protein vaccine in large animals. PMID:24992038

  15. Effects of Bacillus thuringiensis israelensis and spinosad on adult emergence of the non-biting midges Polypedilum nubifer (Skuse) and Tanytarsus curticornis Kieffer (Diptera: Chironomidae) in coastal wetlands.

    PubMed

    Duchet, Claire; Franquet, Evelyne; Lagadic, Laurent; Lagneau, Christophe

    2015-05-01

    To optimize their efficacy, some insecticides used for mosquito control are introduced into aquatic ecosystems where mosquito larvae develop (marshes, ponds, sanitation devices) and cannot escape from the treated water. However, this raises the question of possible effects of mosquito larvicides on non-target aquatic species. Bacillus thuringiensis var. israelensis (Bti), which is well-known for its selectivity for Nematocera dipterans, is widely used for mosquito control all over the world. Spinosad, a mixture of spinosyns A and D known as fermentation products of a soil actinomycete (Saccharopolyspora spinosa), is a biological neurotoxic insecticide with a broader action spectrum. It is a candidate larvicide for mosquito control, but some studies showed that it may be toxic to beneficial or non-target species, including non-biting midges. The present study was therefore undertaken to assess the impact of Bti and spinosad on natural populations of Polypedilum nubifer (Skuse) and Tanytarsus curticornis Kieffer (Diptera: Chironomidae) in field enclosures implemented in Mediterranean coastal wetlands. Unlike Bti, spinosad had a strong lethal effect on P. nubifer and seems to affect T. curticornis at presumed recommended rates for field application. Differences in the sensitivity of these two species to spinosad confirm that population dynamics need to be known for a proper assessment of the risk encountered by chironomids in wetlands where larvicide-based mosquito control occurs. PMID:25728359

  16. Contaminants in stream sediments from seven United States metropolitan areas: part II—sediment toxicity to the amphipod Hyalella azteca and the midge Chironomus dilutus

    USGS Publications Warehouse

    Kemble, Nile E.; Hardesty, Douglas K.; Ingersoll, Christopher G.; Kunz, James L.; Sibley, Paul K.; Calhoun, Daniel L.; Gilliom, Robert J.; Kuivila, Kathryn M.; Nowell, Lisa H.; Moran, Patrick W.

    2013-01-01

    Pyrethroids are hydrophobic compounds that have been observed to accumulate in sediments (Laskowski 2002). Toxicity of pyrethroids in field-collected sediment from small urban streams (Weston et al. 2005; Holmes et al. 2008; Ding et al. 2010; Domagalski et al. 2010) or with pyrethroids spiked into sediment (Amweg et al. 2006; Hintzen et al. 2009) have been evaluated primarily in 10 day lethality tests conducted with the amphipod Hyalella azteca. However, the sublethal effects in long-term exposures to pyrethroids in sediment have not been evaluated, and the distribution of pyrethroids sediments has not typically been evaluated in wadeable streams (Gilliom et al. 2006). This article is the second in a series that describe the results of a study of the distribution and toxicity of pyrethroids and other co-occurring trace elements and organic contaminants (PCBs, PAHs, OC pesticides) in stream sediments from 7 metropolitan areas across the United States (Moran et al. 2012). The study evaluated 98 sediment samples collected from streams ranging from undeveloped to highly urban and differs from previous studies by sampling larger wadeable streams and avoiding point sources (such as storm drains) and other inflows (Gilliom et al. 2006). Part 1 of the series characterizes sediment contaminants in relation to urbanization and other factors in the 7 metropolitan study areas (Nowell et al. 2012). Part 2 (this article) evaluates relationships between sediment chemistry and sediment toxicity in 28 day whole-sediment exposures conducted with the amphipod H. azteca and in 10 day whole-sediment exposure conducted with the midge Chironomus dilutus (USEPA U

  17. Effects of carbamazepine and two of its metabolites on the non-biting midge Chironomus riparius in a sediment full life cycle toxicity test.

    PubMed

    Heye, Katharina; Becker, Dennis; Lütke Eversloh, Christian; Durmaz, Vedat; Ternes, Thomas A; Oetken, Matthias; Oehlmann, Jörg

    2016-07-01

    The antiepileptic drug carbamazepine (CBZ) and its main metabolites carbamazepine-10,11-epoxide (EP-CBZ) and 10,11-dihydro-10,11-dihydroxy-carbamazepine (DiOH-CBZ) were chosen as test substances to assess chronic toxicity on the non-biting midge Chironomus riparius. All the three substances were tested in a 40-day sediment full life cycle test (according to OECD 233) in which mortality, emergence, fertility, and clutch size were evaluated. In addition, these parameters were considered to calculate the population growth rate which represents an integrated measure to assess population relevant effects. With an LC50 of 0.20 mg/kg (time-weighted mean), the metabolite EP-CBZ was significantly more toxic than the parent substance CBZ (LC50: 1.1 mg/kg). Especially mortality, emergence, and fertility showed to be sensitive parameters under the exposure to CBZ and EP-CBZ. By using classical molecular dynamics (MD) simulations, the binding of CBZ to the ecdysone receptor was investigated as one possible mode of action (MoA) but appeared to be unlikely. The second metabolite DiOH-CBZ did not cause any effects within the tested concentration rage (0.17-1.2 mg/kg). Even though CBZ was less toxic compared to EP-CBZ, CBZ is found in the environment at much higher concentrations and therefore causes a higher potential risk for sediment dwelling organisms compared to its metabolites. Nevertheless, the current study illustrates the importance of including commonly found metabolites into the risk assessment of parent substances. PMID:27064208

  18. Host and Potential Vector Susceptibility to an Emerging Orbivirus in the United States: Epizootic Hemorrhagic Disease Virus Serotype 6

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Epizootic hemorrhagic disease (EHD) viruses (EHDV) are orbiviruses transmitted by Culicoides biting midges to domestic and wild ruminants. EHDV-1 and -2 are enzootic in the U.S., where EHD is the most significant viral disease of white-tailed deer (WTD; Odocoileus virginianus) and reports of EHD in ...

  19. Susceptibility of North American white-tailed deer to the Netherlands strain of BTV serotype 8

    Technology Transfer Automated Retrieval System (TEKTRAN)

    World-wide there are at least 24 serotypes of bluetongue virus (BTV), a complex non-enveloped virus in the family Reoviridae, genus Orbivirus. Bluetongue (BT) is an arthropod-borne disease of cattle, sheep, goats, and deer and is transmitted by Culicoides biting midges. In 2006, bluetongue serotype ...

  20. Whole-body distribution an Malpighian tubule transport of 2',5-dichloro-4'-nitrosalicylanilide (Bayer 73) and 3-trifluoromethyl-4-nitrophenol in larvae of the aquatic midge Chironomus tentans.

    PubMed

    Hansen, C R; Gauss, J D; Kawatski, J A

    1980-04-01

    1. Residues of the lampricides 14C-Bayer 73 (2',5-dichloro-4'-nitrosalicylanilide) and 14C-TFM (3-trifluoromethyl-4-nitrophenol) were absorbed from aqueous sublethal concn. by aquatic larvae of the midge Chironomus tentans. 2. Toxicant residues were widely distributed during early hours of exposure, but later and during a 24-h post-exposure period, they became concentrated in the trunk and intestinal tract; the posterior movement of Bayer 73 was more rapid than that of TFM. 3. During 4-h tests, Malpighian tubules of the chironomid actively transported Bayer 73 and TFM in vitro, and on a per tubule basis, more TFM was transported than Bayer 73. 4. Potassium cyanide inhibited tubule transport; serotonin had no effect. PMID:7415206

  1. Anthropogenic and meteorological factors influence vector abundance and prevalence of bluetongue virus infection of dairy cattle in California.

    PubMed

    Mayo, Christie E; Gardner, Ian A; Mullens, Bradley A; Barker, Christopher M; Gerry, Alec C; Guthrie, Alan J; MacLachlan, N James

    2012-03-23

    Bluetongue is an economically important arboviral disease of ruminants that is transmitted by hematophagous Culicoides midges. In light of dramatic recent changes in the global distribution of bluetongue virus (BTV), the goals of this study were to re-evaluate the prevalence of BTV infection of cattle and abundance of Culicoides midges on individual dairy farms in California. A serosurvey of adult dairy cattle confirmed that BTV infection is prevalent throughout much of the state, although the coastal northwestern region remains free of infection and prevalence varies markedly among farms in the remainder of the state. Intensive sampling for one year of 4 farms in the northern Central Valley of California showed that the abundance of Culicoides midges was markedly different and coincided with the prevalence of BTV infection of sentinel cattle on each farm. Mean maximum and minimum temperatures and other meteorological parameters were similar on all 4 farms, thus we speculate that particular management practices were responsible for both the increased midge abundance and prevalence of BTV infection of cattle at individual farms. Specifically, it is concluded that variation in vector abundance at individual farms most likely is the result of waste-water lagoon and irrigation management practices, leading to higher BTV infection rates among livestock held on farms with more waste-water lagoons and greater acreage of land for waste-water irrigation. PMID:21930352

  2. Allatostatin A-like immunoreactivity in the nervous system and gut of the larval midge Chironomus riparius: modulation of hindgut motility, rectal K+ transport and implications for exposure to salinity.

    PubMed

    Robertson, Lisa; Chasiotis, Helen; Galperin, Vladimir; Donini, Andrew

    2014-11-01

    Evidence for the presence of allatostatin (AST) A-like neuropeptides in the larval midge Chironomus riparius is reported. Immunohistochemical studies on the nervous system and gut revealed the presence of AST A-like immunoreactive (AST-IR) cells and processes. The nerve cord contained AST-IR processes that originated from cells in the brain and travelled the length of nerve cord to the terminal ganglion. Within each ganglion, these processes gave rise to varicosities, suggesting that they formed synapses with neurons in the ganglia. Endocrine cells containing AST-IR were present in three regions of the midgut: near the attachment of the Malpighian tubules, between the anterior and posterior midgut, and in the vicinity of the gastric caecae. The terminal ganglion also contained four AST-IR cells that gave rise to axons that projected onto the hindgut and posterior midgut. Application of a cockroach AST to the semi-isolated hindgut of larval C. riparius led to dose-dependent inhibition of muscle contractions with an EC50 of ~10 nmol l(-1) and a decrease in rectal K(+) reabsorption resulting from reduced rectal Na(+)/K(+)-ATPase and vacuolar type H(+)-ATPase activities. The results suggest the presence of endogenous AST-like neuropeptides in larval C. riparius, where these factors play a role in the function of the gut. Furthermore, regulation of ion reabsorption by ASTs at the rectum could serve as an ideal mechanism of ion regulation in the face of abrupt and acute elevated salt levels. PMID:25214489

  3. Bluetongue disease in Germany (2007-2008): monitoring of entomological aspects.

    PubMed

    Mehlhorn, Heinz; Walldorf, Volker; Klimpel, Sven; Schaub, Günter; Kiel, Ellen; Focke, René; Liebisch, Gabriele; Liebisch, Arndt; Werner, Doreen; Bauer, Christian; Clausen, Henning; Bauer, Burkhard; Geier, Martin; Hörbrand, Thomas; Bätza, Hans-Joachim; Conraths, Franz J; Hoffmann, Bernd; Beer, Martin

    2009-08-01

    In the summer of 2006, a bluetongue epidemic started in the border area of Belgium, The Netherlands, and Germany, spread within 2 years over large areas of Western and Central Europe, and caused substantial losses in farm ruminants. Especially sheep and cattle were severely affected, leading to a case-fatality ratio of nearly 40% in sheep (Conraths et al., Emerg Inf Dis 15(3):433-435, 2009). The German federal ministry of food, agriculture, and consumer protection (BMELV) established a countrywide monitoring on the occurrence of the vectors of this virus, i.e., midges (family Ceratopogonidae) of the genus Culicoides. The monitoring was done on 91 sites, most of which were localized in the 150-km restriction zone that existed in December 2006. A grid consisting of 45 x 45 km(2) cells was formed that covered the monitoring area. As a rule, one trap was placed into each grid cell. The monitoring program started at the end of March 2007 and lasted until May 2008. It included the catching of midges by ultraviolet light traps-done each month from days 1 until 8, the selection of midges of the Culicoides obsoletus, Culicoides pulicaris group, and other Culicoides spp., the testing of midges for bluetongue virus (BTV) by polymerase chain reaction (PCR), and the daily registration of weather data at each trap site for the whole monitoring period. The following main results were obtained: (1) Members of the C. obsoletus group were most commonly found in the traps, reaching often 3/4 of the catches. The African and South European vector of BTV-the species Culicoides imicola-was never found. (2) Members of the C. obsoletus group were most frequently found infected with BTV besides a few cases in the C. pulicaris group and other species. (3) Members of the C. obsoletus group were also found in winter. Their numbers were reduced, however, and they were caught mostly close to stables. Therefore, a true midge-free period does not exist during the year in Germany. (4) The amounts

  4. Sorghum Midge Resistance in Grain Sorghum Hybrids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although grain sorghum is a good rotation crop, the plants are impacted by a variety of insects and pathogens from the seedling stage through maturity in the Coastal Plain region. Nine insect pests of sorghum in southern Georgia were detected in 2006. They were, in order of importance: sorghum mid...

  5. Epidemiology of bluetongue and related orbiviruses in the Sultanate of Oman.

    PubMed Central

    al-Busaidy, S. M.; Mellor, P. S.

    1991-01-01

    Sentinel herds at 34 farms were used to study the epidemiology of bluetongue and related orbiviruses in Oman. The results indicate that bluetongue virus (BTV) is widespread and is enzootic in Northern Oman. At least three BTV serotypes (3, 4 and 22) were present at the time of the study. Antibodies to epizootic haemorrhagic disease of deer virus (EHDV) type 2 and EHDV-318 were also detected but were less prevalent. Entomological investigations identified the presence of 16 species of Culicoides. The peak seasonal incidence of the BTV vector C. imicola and the EHDV vectors C. schultzei (group) midges at Rumais in Northern Oman correlated closely with the spring rains in that area. However, both species of midge were also present in lower numbers throughout the year. four species of Oman midge, C. arabiensis, C. ibriensis, C. neoschultzei and C. buettikeri are new to science. PMID:1847102

  6. Evaluation of toxicity to the amphipod, Hyalella azteca, and to the midge, Chironomus dilutus; and bioaccumulation by the oligochaete, Lumbriculus variegatus, with exposure to PCB-contaminated sediments from Anniston, Alabama

    USGS Publications Warehouse

    Ingersoll, Christopher G.; Steevens, Jeffery A.; MacDonald, Donald D.; Brumbaugh, William G.; Coady, Matthew R.; Farrar, J. Daniel; Lotufo, Guilherme R.; Kemble, Nile E.; Kunz, James L.; Stanley, Jacob K.; Sinclair, Jesse A.

    2014-01-01

    The U.S. Environmental Protection Agency (USEPA) requested that as part of the remedial investigation for the Anniston, Alabama Polychlorinated Biphenyl (PCB) Site (Anniston PCB Site), that Pharmacia Corporation and Solutia Inc. (P/S) perform long-term reproduction toxicity tests with the amphipod, Hyalella azteca, and the midge, Chironomus dilutus, and bioaccumulation tests with the oligochaete, Lumbriculus variegatus, using sediment samples collected from reference locations and from Operable Unit 4 of the Anniston PCB Site. The sediment toxicity testing and sediment bioaccumulation results will be used by ARCADIS U.S., Inc. (ARCADIS) as part of a weight-of-evidence assessment to evaluate risks and establish sediment remediation goals for contaminants to sediment-dwelling organisms inhabiting the Anniston PCB Site. The goal of this study was to characterize relations between sediment chemistry and sediment toxicity and relations between sediment chemistry and sediment bioaccumulation in samples of sediments collected from the Anniston PCB Site. A total of 32 samples were evaluated from six test sites and one reference site to provide a wide range in concentrations of chemicals of potential concern (COPCs) including PCBs in samples of whole sediment. The goal of this study was not to determine the extent of sediment contamination across the Anniston PCB Site. Hence, the test sites or samples collected from within a test site were not selected to represent the spatial extent of sediment contamination across the Anniston PCB Site. Sediment chemistry, pore-water chemistry, and sediment toxicity data were generated for 26 sediment samples from the Anniston PCB Site. All of the samples were evaluated to determine if they qualified as reference sediment samples. Those samples that met the chemical selection criteria and biological selection criteria were identified as reference samples and used to develop the reference envelope for each toxicity test endpoint. Physical

  7. Schmallenberg virus in Germany 2011-2014: searching for the vectors.

    PubMed

    Kameke, Daniela; Werner, Doreen; Hoffmann, Bernd; Lutz, Walburga; Kampen, Helge

    2016-02-01

    Following the emergence of Schmallenberg virus (SBV) in 2011, 21,397 culicoid biting midges (Diptera: Ceratopogonidae) from targeted and non-targeted sampling activities carried out during the summer months of 2011 to 2013 and in late 2014 in various regions in Germany were analyzed for the virus by real-time RT-PCR. While no SBV was found in biting midges collected during 2011 and 2013, 2 out of 334 pools including 20 and 22 non-engorged females of the Obsoletus complex sampled in 2012 tested positive for the SBV S-segment with C(t) values of 42.46 and 35.45. In addition, 673 black flies (Diptera: Simuliidae) captured during the same studies were screened for the presence of SBV and proved negative. In late autumn 2014, biting midges were collected again in a limited study in eastern Germany after some cases of SBV infection had occurred in a quarantine station for cattle. Due to the unfavorable seasonal weather conditions, only few specimens were caught, and these were also negative for SBV. The German experience suggests that biting midge collections launched only after an outbreak and are not locally targeted may be ineffective as to virus detection. It rather might be advisable to collect biting midges at sentinel farms on a permanent basis so to have material available to be examined in the case of a disease outbreak. PMID:26462800

  8. A preliminary survey of the epidemiology of bluetongue in Kenya

    PubMed Central

    Walker, A. R.; Davies, F. G.

    1971-01-01

    A survey of the species composition and distribution of the Culicoides midge populations at a range of sites where bluetongue is enzootic isolated a group of dominant species: C. cornutus, C. grahamii, C. magnus, C. milnei, C. pallidipennis and C. 23. † Monthly light-trap sampling of Culicoides showed that the population densities of the dominant species greatly increased after the rain seasons and that these species concentrated around flocks of sheep and cattle. The larval habitats of C. cornutus and C. pallidipennis were found associated with stock pens. Precipitin tests on blood-fed Culicoides showed that most of the dominant species regularly feed on sheep and cattle. Bluetongue virus was isolated from C. milnei, C. pallidipennis and C. 23. Serological surveys of wild and domestic bovids from the enzootic area showed a high proportion with antibody to bluetongue virus. The colonization of C. cornutus, a potential vector, is described briefly. A causal relationship between peak rainfall in April—May, peak numbers of Culicoides in May—June and peak bluetongue incidence in June—July is postulated. The vector status of the above species and C. austeni was evaluated. PMID:4337112

  9. Bluetongue Virus Serotype 1 Outbreak in the Basque Country (Northern Spain) 2007–2008. Data Support a Primary Vector Windborne Transport

    PubMed Central

    García-Lastra, Rodrigo; Leginagoikoa, Iratxe; Plazaola, Jose M.; Ocabo, Blanca; Aduriz, Gorka; Nunes, Telmo; Juste, Ramón A.

    2012-01-01

    Background Bluetongue (BT) is a vector-borne disease of ruminants that has expanded its traditional global distribution in the last decade. Recently, BTV-1 emerged in Southern Spain and caused several outbreaks in livestock reaching the north of the country. The aim of this paper was to review the emergence of BTV-1 in the Basque Country (Northern Spain) during 2007 and 2008 analyzing the possibility that infected Culicoides were introduced into Basque Country by winds from the infected areas of Southern Spain. Methodology/Principal Findings We use a complex HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) model to draw wind roses and backward wind trajectories. The analysis of winds showed September 28 to October 2 as the only period for the introduction of infected midges in the Basque Country. These wind trajectories crossed through the areas affected by serotype 1 on those dates in the South of the Iberian Peninsula. Additionally meteorological data, including wind speed and humidity, and altitude along the trajectories showed suitable conditions for Culicoides survival and dispersion. Conclusions/Significance An active infection in medium-long distance regions, wind with suitable speed, altitude and trajectory, and appropriate weather can lead to outbreaks of BTV-1 by transport of Culicoides imicola, not only over the sea (as reported previously) but also over the land. This shows that an additional factor has to be taken into account for the control of the disease which is currently essentially based on the assumption that midges will only spread the virus in a series of short hops. Moreover, the epidemiological and serological data cannot rule out the involvement of other Culicoides species in the spread of the infection, especially at a local level. PMID:22479628

  10. Schmallenberg virus infection.

    PubMed

    Wernike, K; Elbers, A; Beer, M

    2015-08-01

    Since Schmallenberg virus, an orthobunyavirus of the Simbu serogroup, was identified near the German-Dutch border for the first time in late 2011 it has spread extremely quickly and caused a large epidemic in European livestock. The virus, which is transmitted by Culicoides biting midges, infects domestic and wild ruminants. Adult animals show only mild clinical symptoms or none at all, whereas an infection during a critical period of gestation can lead to abortion, stillbirth or the birth of severely malformed offspring. The impact of the disease is usually greater in sheep than in cattle. Vaccination could be an important aspect of disease control. PMID:26601441

  11. Mansonelliasis, a neglected parasitic disease in Haiti

    PubMed Central

    Raccurt, Christian Pierre; Brasseur, Philippe; Boncy, Jacques

    2014-01-01

    Reported in Haiti as early as 1923, Mansonella ozzardi is still a neglected disease ignored by the health authorities of the country. This review is an update on the geographic distribution of the coastal foci of mansonelliasis in Haiti, the epidemiological profile and prevalence rates of microfilariae in people living in endemic areas, the clinical impact of the parasite on health and the efficiency of the transmission of the parasite among three Culicoides biting-midge species identified as vectors in Haiti. Additionally, interest in establishing a treatment programme to combat this parasite using a single dose of ivermectin is emphasised. PMID:25317697

  12. Summer eczema in exported Icelandic horses: influence of environmental and genetic factors

    PubMed Central

    Björnsdóttir, Sigríður; Sigvaldadóttir, Jakobína; Broström, Hans; Langvad, Birgitte; Sigurðsson, Ágúst

    2006-01-01

    A cross sectional study was designed to estimate the prevalence of summer eczema (a chronic, recurrent seasonal dermatitis) in exported Icelandic horses and the influence of environmental and genetic factors on the development of the disease. Among 330 horses, which had been exported to Germany, Denmark and Sweden, 114 (34.5%) were found to have clinical signs of summer eczema. The prevalence was highest 2 years after export and the exposure to the biting midges Culicoides spp., was found to be the main risk factor for developing the disease. Genetic influence on the sensitivity for the disease was not established. It was concluded that exported Icelandic horses are predisposed for summer dermatitis and the fact that they are not introduced to the antigens of the biting midges early in live, due to it's absence in Iceland, is likely to explain the high prevalence of the disease after export. PMID:16987399

  13. Sorghum Midge Resistance in 16 Grain Sorghum Hybrids - 2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grain sorghum is a good dryland rotation crop in the southern Coastal Plain region, where it is impacted by a variety of insects and pathogens from the seedling stage through maturity. Diseases were of minimal importance in 2008. Ten insect pests of sorghum were recorded in southern Georgia in 2008...

  14. Rearing and Maintaining Midge Cultures (Chironomus tentans) for Laboratory Studies.

    ERIC Educational Resources Information Center

    Hein, John; Mahadeva, Madhu N.

    1992-01-01

    The life history of the Chironomus tentans can be observed in easily established and maintained laboratory cultures. Projects for the classroom include observing hydration of an egg mass; embryonic development, hatching and larval feeding; larval activity; and mating activity. (MDH)

  15. Integrated Taxonomy and DNA Barcoding of Alpine Midges (Diptera: Chironomidae)

    PubMed Central

    Montagna, Matteo; Mereghetti, Valeria; Lencioni, Valeria; Rossaro, Bruno

    2016-01-01

    Rapid and efficient DNA-based tools are recommended for the evaluation of the insect biodiversity of high-altitude streams. In the present study, focused principally on larvae of the genus Diamesa Meigen 1835 (Diptera: Chironomidae), the congruence between morphological/molecular delimitation of species as well as performances in taxonomic assignments were evaluated. A fragment of the mitochondrial cox1 gene was obtained from 112 larvae, pupae and adults (Diamesinae, Orthocladiinae and Tanypodinae) that were collected in different mountain regions of the Alps and Apennines. On the basis of morphological characters 102 specimens were attributed to 16 species, and the remaining ten specimens were identified to the genus level. Molecular species delimitation was performed using: i) distance-based Automatic Barcode Gap Discovery (ABGD), with no a priori assumptions on species identification; and ii) coalescent tree-based approaches as the Generalized Mixed Yule Coalescent model, its Bayesian implementation and Bayesian Poisson Tree Processes. The ABGD analysis, estimating an optimal intra/interspecific nucleotide distance threshold of 0.7%-1.4%, identified 23 putative species; the tree-based approaches, identified between 25–26 entities, provided nearly identical results. All species belonging to zernyi, steinboecki, latitarsis, bertrami, dampfi and incallida groups, as well as outgroup species, are recovered as separate entities, perfectly matching the identified morphospecies. In contrast, within the cinerella group, cases of discrepancy arose: i) the two morphologically separate species D. cinerella and D. tonsa are neither monophyletic nor diagnosable exhibiting low values of between-taxa nucleotide mean divergence (0.94%); ii) few cases of larvae morphological misidentification were observed. Head capsule color is confirmed to be a valid character able to discriminate larvae of D. zernyi, D. tonsa and D. cinerella, but it is here better defined as a color gradient between the setae submenti and genal setae. DNA barcodes performances were high: average accuracy was ~89% and precision of ~99%. On the basis of the present data, we can thus conclude that molecular identification represents a promising tool that could be effectively adopted in evaluating biodiversity of high-altitude streams. PMID:26938660

  16. Integrated Taxonomy and DNA Barcoding of Alpine Midges (Diptera: Chironomidae).

    PubMed

    Montagna, Matteo; Mereghetti, Valeria; Lencioni, Valeria; Rossaro, Bruno

    2016-01-01

    Rapid and efficient DNA-based tools are recommended for the evaluation of the insect biodiversity of high-altitude streams. In the present study, focused principally on larvae of the genus Diamesa Meigen 1835 (Diptera: Chironomidae), the congruence between morphological/molecular delimitation of species as well as performances in taxonomic assignments were evaluated. A fragment of the mitochondrial cox1 gene was obtained from 112 larvae, pupae and adults (Diamesinae, Orthocladiinae and Tanypodinae) that were collected in different mountain regions of the Alps and Apennines. On the basis of morphological characters 102 specimens were attributed to 16 species, and the remaining ten specimens were identified to the genus level. Molecular species delimitation was performed using: i) distance-based Automatic Barcode Gap Discovery (ABGD), with no a priori assumptions on species identification; and ii) coalescent tree-based approaches as the Generalized Mixed Yule Coalescent model, its Bayesian implementation and Bayesian Poisson Tree Processes. The ABGD analysis, estimating an optimal intra/interspecific nucleotide distance threshold of 0.7%-1.4%, identified 23 putative species; the tree-based approaches, identified between 25-26 entities, provided nearly identical results. All species belonging to zernyi, steinboecki, latitarsis, bertrami, dampfi and incallida groups, as well as outgroup species, are recovered as separate entities, perfectly matching the identified morphospecies. In contrast, within the cinerella group, cases of discrepancy arose: i) the two morphologically separate species D. cinerella and D. tonsa are neither monophyletic nor diagnosable exhibiting low values of between-taxa nucleotide mean divergence (0.94%); ii) few cases of larvae morphological misidentification were observed. Head capsule color is confirmed to be a valid character able to discriminate larvae of D. zernyi, D. tonsa and D. cinerella, but it is here better defined as a color gradient between the setae submenti and genal setae. DNA barcodes performances were high: average accuracy was ~89% and precision of ~99%. On the basis of the present data, we can thus conclude that molecular identification represents a promising tool that could be effectively adopted in evaluating biodiversity of high-altitude streams. PMID:26938660

  17. Monitoring With Midges: Body Size, Bias and Biomonitoring.

    NASA Astrophysics Data System (ADS)

    Gresens, S. E.; Ferrington, L. C.

    2005-05-01

    Effective use of Chironomidae in biological monitoring programs requires accurate assessments of taxonomic composition and relative abundance. Simultaneous collections of surface-floating pupal exuviae (SFPE) and d-net samples for larvae (DNL) in studies based in Pennsylvania and Kansas reveals that samples of SFPE consistently result in higher species richness estimates and differing patterns of taxonomic composition and relative abundance, especially for smaller species (ie., maximum larval length of 5-6 mm). Calculations of Biotic Index values (BI) yield higher values for DNL than SFPE, primarily related to increased tolerances to lower dissolved Oxygen of larger species of Chironomini (maximum larval length greater than 10 mm) in DNL. Simulations employing selective deletions of smaller species from SFPE samples collected from several sample sites in Minnehaha Creek (MN) substantially increase calculated BI values, in some cases 2-3 points. We conclude that under-representation of smaller species in DNL samples can be a wide-spread and pervasive problem that results in inflated BI values, which can lead to inaccurate judgments regarding water quality. These results, combined with previous studies indicating that SFPE are more cost-efficient to process and quantify, clearly demonstrate that SFPE should be integrated into biological monitoring programs if Chironomidae are to be properly utilized.

  18. VP2 Exchange and NS3/NS3a Deletion in African Horse Sickness Virus (AHSV) in Development of Disabled Infectious Single Animal Vaccine Candidates for AHSV

    PubMed Central

    van de Water, Sandra G. P.; van Gennip, René G. P.; Potgieter, Christiaan A.; Wright, Isabel M.

    2015-01-01

    ABSTRACT African horse sickness virus (AHSV) is a virus species in the genus Orbivirus of the family Reoviridae. There are nine serotypes of AHSV showing different levels of cross neutralization. AHSV is transmitted by species of Culicoides biting midges and causes African horse sickness (AHS) in equids, with a mortality rate of up to 95% in naive horses. AHS has become a serious threat for countries outside Africa, since endemic Culicoides species in moderate climates appear to be competent vectors for the related bluetongue virus (BTV). To control AHS, live-attenuated vaccines (LAVs) are used in Africa. We used reverse genetics to generate “synthetic” reassortants of AHSV for all nine serotypes by exchange of genome segment 2 (Seg-2). This segment encodes VP2, which is the serotype-determining protein and the dominant target for neutralizing antibodies. Single Seg-2 AHSV reassortants showed similar cytopathogenic effects in mammalian cells but displayed different growth kinetics. Reverse genetics for AHSV was also used to study Seg-10 expressing NS3/NS3a proteins. We demonstrated that NS3/NS3a proteins are not essential for AHSV replication in vitro. NS3/NS3a of AHSV is, however, involved in the cytopathogenic effect in mammalian cells and is very important for virus release from cultured insect cells in particular. Similar to the concept of the bluetongue disabled infectious single animal (BT DISA) vaccine platform, an AHS DISA vaccine platform lacking NS3/NS3a expression was developed. Using exchange of genome segment 2 encoding VP2 protein (Seg-2[VP2]), we will be able to develop AHS DISA vaccine candidates for all current AHSV serotypes. IMPORTANCE African horse sickness virus is transmitted by species of Culicoides biting midges and causes African horse sickness in equids, with a mortality rate of up to 95% in naive horses. African horse sickness has become a serious threat for countries outside Africa, since endemic Culicoides species in moderate

  19. Bluetongue.

    PubMed

    Maclachlan, N J; Mayo, C E; Daniels, P W; Savini, G; Zientara, S; Gibbs, E P J

    2015-08-01

    Summary Bluetongue (BT) is an arthropod-transmitted viral disease of non-African ungulates, principally sheep. The disease results from vascular injury analogous to that of human haemorrhagic viral fevers, with characteristic tissue infarction, haemorrhage, vascular leakage, oedema, and hypovolaemic shock. Importantly, BT is not zoonotic. Bluetongue virus (BTV) infection of ruminants and vector Culicoides midges is endemic throughout many tropical and temperate regions of the world; however, within this global range the virus exists within relatively discrete ecosystems (syn. episystems) where specific constellations of BTV serotypes are spread by different species of biting Culicoides midges. Recently discovered goat-associated BTVs, notably BTV serotype 25 (BTV-25) in central Europe, appear to have distinctive biological properties and an epidemiology that is not reliant on Culicoides midges as vectors for virus transmission. Bluetongue virus infection of ruminants is often subclinical, but outbreaks of severe disease occur regularly at the upper and lower limits of the virus's global range, where infection is distinctly seasonal. There have been recent regional alterations in the global distribution of BTV infection, particularly in Europe. It is proposed that climate change is responsible for these events through its impact on vector midges. However, the role of anthropogenic factors in mediating emergence of BTV into new areas remains poorly defined; for example, it is not clear to what extent anthropogenic factors were responsible for the recent translocation to northern and eastern Europe of live attenuated vaccine viruses and an especially virulent strain of BTV-8 with distinctive properties. Without thorough characterisation of all environmental and anthropogenic drivers of the recent emergence of BT in northern Europe and elsewhere, it is difficult to predict what the future holds in terms of global emergence of BTV infection. Accurate and convenient

  20. Turnover Rate of NS3 Proteins Modulates Bluetongue Virus Replication Kinetics in a Host-Specific Manner

    PubMed Central

    Ftaich, Najate; Ciancia, Claire; Viarouge, Cyril; Barry, Gerald; Ratinier, Maxime; van Rijn, Piet A.; Breard, Emmanuel; Vitour, Damien; Zientara, Stephan; Palmarini, Massimo; Terzian, Christophe

    2015-01-01

    ABSTRACT Bluetongue virus (BTV) is an arbovirus transmitted to livestock by midges of the Culicoides family and is the etiological agent of a hemorrhagic disease in sheep and other ruminants. In mammalian cells, BTV particles are released primarily by virus-induced cell lysis, while in insect cells they bud from the plasma membrane and establish a persistent infection. BTV possesses a ten-segmented double-stranded RNA genome, and NS3 proteins are encoded by segment 10 (Seg-10). The viral nonstructural protein 3 (NS3) plays a key role in mediating BTV egress as well as in impeding the in vitro synthesis of type I interferon in mammalian cells. In this study, we asked whether genetically distant NS3 proteins can alter BTV-host interactions. Using a reverse genetics approach, we showed that, depending on the NS3 considered, BTV replication kinetics varied in mammals but not in insects. In particular, one of the NS3 proteins analyzed harbored a proline at position 24 that leads to its rapid intracellular decay in ovine but not in Culicoides cells and to the attenuation of BTV virulence in a mouse model of disease. Overall, our data reveal that the genetic variability of Seg-10/NS3 differentially modulates BTV replication kinetics in a host-specific manner and highlight the role of the host-specific variation in NS3 protein turnover rate. IMPORTANCE BTV is the causative agent of a severe disease transmitted between ruminants by biting midges of Culicoides species. NS3, encoded by Seg-10 of the BTV genome, fulfills key roles in BTV infection. As Seg-10 sequences from various BTV strains display genetic variability, we assessed the impact of different Seg-10 and NS3 proteins on BTV infection and host interactions. In this study, we revealed that various Seg-10/NS3 proteins alter BTV replication kinetics in mammals but not in insects. Notably, we found that NS3 protein turnover may vary in ovine but not in Culicoides cells due to a single amino acid residue that, most

  1. Adaptive strategies of African horse sickness virus to facilitate vector transmission

    PubMed Central

    Wilson, Anthony; Mellor, Philip Scott; Szmaragd, Camille; Mertens, Peter Paul Clement

    2009-01-01

    African horse sickness virus (AHSV) is an orbivirus that is usually transmitted between its equid hosts by adult Culicoides midges. In this article, we review the ways in which AHSV may have adapted to this mode of transmission. The AHSV particle can be modified by the pH or proteolytic enzymes of its immediate environment, altering its ability to infect different cell types. The degree of pathogenesis in the host and vector may also represent adaptations maximising the likelihood of successful vectorial transmission. However, speculation upon several adaptations for vectorial transmission is based upon research on related viruses such as bluetongue virus (BTV), and further direct studies of AHSV are required in order to improve our understanding of this important virus. PMID:19094921

  2. Evidence of excretion of Schmallenberg virus in bull semen

    PubMed Central

    2014-01-01

    Schmallenberg virus (SBV) is a novel orthobunyavirus, discovered in Germany in late 2011. It mainly infects cattle, sheep and goats and could lead to congenital infection, causing abortion and fetal abnormalities. SBV is transmitted by biting midges from the Culicoides genus and there is no evidence that natural infection occurs directly between ruminants. Here, we could detect SBV RNA in infected bull semen using qRT-PCR (three bulls out of seven tested positive; 29 positive semen batches out of 136). We also found that highly positive semen batches from SBV infected bulls can provoke an acute infection in IFNAR-/- mice, suggesting the potential presence of infectious virus in the semen of SBV infected bulls. PMID:24708245

  3. Malakal virus from Africa and Kimberley virus from Australia are geographic variants of a widely distributed ephemerovirus.

    PubMed

    Blasdell, Kim R; Voysey, Rhonda; Bulach, Dieter M; Trinidad, Lee; Tesh, Robert B; Boyle, David B; Walker, Peter J

    2012-11-10

    Kimberley virus (KIMV) is an arthropod-borne rhabdovirus that was isolated in 1973 and on several subsequent occasions from healthy cattle, mosquitoes (Culex annulirostris) and biting midges (Culicoides brevitarsis) in Australia. Malakal virus (MALV) is an antigenically related rhabdovirus isolated in 1963 from mosquitoes (Mansonia uniformis) in Sudan. We report here the complete genome sequences of KIMV (15442 nt) and MALV (15444 nt). The genomes have a similar organisation (3'-l-N-P-M-G-G(NS)-α1-α2-β-γ-L-t-5') to that of bovine ephemeral fever virus (BEFV). High levels of amino acid identity in each gene, similar gene expression profiles, clustering in phylogenetic analyses of the N, P, G and L proteins, and strong cross-neutralisation indicate that KIMV and MALV are geographic variants of the same ephemerovirus that, like BEFV, occurs in Africa, Asia and Australia. PMID:22925335

  4. Epidemiologic Survey of Mansonella ozzardi in Corail, Haiti

    PubMed Central

    Raccurt, Christian P.; Brasseur, Philippe; Cicéron, Micheline; Boncy, Jacques

    2014-01-01

    An epidemiologic (cross-sectional study) survey on 462 inhabitants in Corail, Haiti showed that 16.5% were infected with Mansonella ozzardi. This finding was determined from a single 20-μL sample of finger prick blood from each person. Among children, < 2% had a detectable microfilaremia. In persons > 15 years of age, the prevalence of infection for males and females was 23% and 21%, respectively. In general, the microfilaremias were low and 70% of positive persons had < 10 microfilariae per 20 μL of blood; only 5% had > 50 microfilariae. This study shows that persons living near mangrove marshes that are breeding sites for Culicoides furens and C. barbosai biting midges, which are recognized vectors of M. ozzardi in Haiti, are consequently more frequently infected than those living in downtown area of Corail or inland. PMID:24710617

  5. Isolation of Bluetongue Virus 24 from India - An Exotic Serotype to Australasia.

    PubMed

    Krishnajyothi, Y; Maan, S; Kandimalla, K; Maan, N S; Tutika, R B; Reddy, Y V; Kumar, A; Mrunalini, N; Reddy, G H; Putty, K; Ahmed, S M; Reddy, Y N; Hemadri, D; Singh, K P; Mertens, P P C; Hegde, N R; Rao, P P

    2016-08-01

    Bluetongue (BT) is a viral disease of ruminants and is caused by different serotypes of bluetongue virus (BTV), which is transmitted by several species of Culicoides midges. The disease is endemic in tropical areas, and incursions have been observed in some of the temperate areas. Twenty-seven recognized serotypes of BTV have been reported so far. Some serotype viruses have been shown to circulate in certain geographical areas. BTV-24 has been reported from Africa, the Mediterranean and the Americas, whereas it is exotic to Australasia. Here, we report isolation of BTV-24 from India and show that it has high sequence homology in genome segment 2 with other Western isolates of BTV-24. Entry of this serotype into Australasian region is a cause of concern. PMID:27241307

  6. A Modified Vaccinia Ankara Virus (MVA) Vaccine Expressing African Horse Sickness Virus (AHSV) VP2 Protects Against AHSV Challenge in an IFNAR −/− Mouse Model

    PubMed Central

    Castillo-Olivares, Javier; Calvo-Pinilla, Eva; Casanova, Isabel; Bachanek-Bankowska, Katarzyna; Chiam, Rachael; Maan, Sushila; Nieto, Jose Maria; Ortego, Javier; Mertens, Peter Paul Clement

    2011-01-01

    African horse sickness (AHS) is a lethal viral disease of equids, which is transmitted by Culicoides midges that become infected after biting a viraemic host. The use of live attenuated vaccines has been vital for the control of this disease in endemic regions. However, there are safety concerns over their use in non-endemic countries. Research efforts over the last two decades have therefore focused on developing alternative vaccines based on recombinant baculovirus or live viral vectors expressing structural components of the AHS virion. However, ethical and financial considerations, relating to the use of infected horses in high biosecurity installations, have made progress very slow. We have therefore assessed the potential of an experimental mouse-model for AHSV infection for vaccine and immunology research. We initially characterised AHSV infection in this model, then tested the protective efficacy of a recombinant vaccine based on modified vaccinia Ankara expressing AHS-4 VP2 (MVA-VP2). PMID:21298069

  7. Using shared needles for subcutaneous inoculation can transmit bluetongue virus mechanically between ruminant hosts

    PubMed Central

    Darpel, Karin E.; Barber, James; Hope, Andrew; Wilson, Anthony J.; Gubbins, Simon; Henstock, Mark; Frost, Lorraine; Batten, Carrie; Veronesi, Eva; Moffat, Katy; Carpenter, Simon; Oura, Chris; Mellor, Philip S.; Mertens, Peter P. C.

    2016-01-01

    Bluetongue virus (BTV) is an economically important arbovirus of ruminants that is transmitted by Culicoides spp. biting midges. BTV infection of ruminants results in a high viraemia, suggesting that repeated sharing of needles between animals could result in its iatrogenic transmission. Studies defining the risk of iatrogenic transmission of blood-borne pathogens by less invasive routes, such as subcutaneous or intradermal inoculations are rare, even though the sharing of needles is common practice for these inoculation routes in the veterinary sector. Here we demonstrate that BTV can be transmitted by needle sharing during subcutaneous inoculation, despite the absence of visible blood contamination of the needles. The incubation period, measured from sharing of needles, to detection of BTV in the recipient sheep or cattle, was substantially longer than has previously been reported after experimental infection of ruminants by either direct inoculation of virus, or through blood feeding by infected Culicoides. Although such mechanical transmission is most likely rare under field condition, these results are likely to influence future advice given in relation to sharing needles during veterinary vaccination campaigns and will also be of interest for the public health sector considering the risk of pathogen transmission during subcutaneous inoculations with re-used needles. PMID:26853457

  8. Using shared needles for subcutaneous inoculation can transmit bluetongue virus mechanically between ruminant hosts.

    PubMed

    Darpel, Karin E; Barber, James; Hope, Andrew; Wilson, Anthony J; Gubbins, Simon; Henstock, Mark; Frost, Lorraine; Batten, Carrie; Veronesi, Eva; Moffat, Katy; Carpenter, Simon; Oura, Chris; Mellor, Philip S; Mertens, Peter P C

    2016-01-01

    Bluetongue virus (BTV) is an economically important arbovirus of ruminants that is transmitted by Culicoides spp. biting midges. BTV infection of ruminants results in a high viraemia, suggesting that repeated sharing of needles between animals could result in its iatrogenic transmission. Studies defining the risk of iatrogenic transmission of blood-borne pathogens by less invasive routes, such as subcutaneous or intradermal inoculations are rare, even though the sharing of needles is common practice for these inoculation routes in the veterinary sector. Here we demonstrate that BTV can be transmitted by needle sharing during subcutaneous inoculation, despite the absence of visible blood contamination of the needles. The incubation period, measured from sharing of needles, to detection of BTV in the recipient sheep or cattle, was substantially longer than has previously been reported after experimental infection of ruminants by either direct inoculation of virus, or through blood feeding by infected Culicoides. Although such mechanical transmission is most likely rare under field condition, these results are likely to influence future advice given in relation to sharing needles during veterinary vaccination campaigns and will also be of interest for the public health sector considering the risk of pathogen transmission during subcutaneous inoculations with re-used needles. PMID:26853457

  9. Wetland cover dynamics drive hemorrhagic disease patterns in white-tailed deer in the United States.

    PubMed

    Berry, Brett S; Magori, Krisztian; Perofsky, Amanda C; Stallknecht, David E; Park, Andrew W

    2013-07-01

    While vector-borne diseases are known to be particularly influenced by environmental factors, the impact of land-cover change on vector-borne wildlife disease patterns is poorly understood, largely due to the paucity of data on disease occurrence at extensive spatial and temporal scales. Widespread and rapid anthropogenic land-cover change, especially urbanization, has transformed the US landscape during the last century. Epizootic hemorrhagic disease virus and blue tongue virus, vectored by Culicoides biting midges, are two RNA viruses in the Orbivirus genus that cause severe hemorrhagic disease (HD) in white-tailed deer (Odocoileus virginianus). We examine the spatial dynamics of HD affecting white-tailed deer in the contiguous United States in two periods covering 1980 to 2007 in connection with land-cover change over the same time. Using spatial statistical modeling, wetland cover emerges as a critical driver of HD morbidity, whereas the drivers of mortality patterns are more complex. Increasing wetland cover is positively associated with HD morbidity, which is consistent with the ecologic requirements of the Culicoides vector. Wetland cover is inherently dynamic due to its importance to biodiversity and water quality as well as its utility for other purposes when drained. Accordingly this analysis helps in understanding the consequences of changing wetlands on vector-borne disease patterns, to identify disease hotspots in a large landscape, and to forecast the spatial spread of HD and related diseases. PMID:23778598

  10. Using remote sensing and machine learning for the spatial modelling of a bluetongue virus vector

    NASA Astrophysics Data System (ADS)

    Van doninck, J.; Peters, J.; De Baets, B.; Ducheyne, E.; Verhoest, N. E. C.

    2012-04-01

    Bluetongue is a viral vector-borne disease transmitted between hosts, mostly cattle and small ruminants, by some species of Culicoides midges. Within the Mediterranean basin, C. imicola is the main vector of the bluetongue virus. The spatial distribution of this species is limited by a number of environmental factors, including temperature, soil properties and land cover. The identification of zones at risk of bluetongue outbreaks thus requires detailed information on these environmental factors, as well as appropriate epidemiological modelling techniques. We here give an overview of the environmental factors assumed to be constraining the spatial distribution of C. imicola, as identified in different studies. Subsequently, remote sensing products that can be used as proxies for these environmental constraints are presented. Remote sensing data are then used together with species occurrence data from the Spanish Bluetongue National Surveillance Programme to calibrate a supervised learning model, based on Random Forests, to model the probability of occurrence of the C. imicola midge. The model will then be applied for a pixel-based prediction over the Iberian peninsula using remote sensing products for habitat characterization.

  11. Effects of aerial applications of naled on nontarget insects at Parris Island, South Carolina.

    PubMed

    Breidenbaugh, M S; de Szalay, F A

    2010-04-01

    Testing impacts of large-scale aerial spraying to control public health pests under realistic field conditions are needed to understand impacts on natural populations of nontarget insects. Responses of terrestrial insects to aerial applications of an organophosphate insecticide, naled, used for mosquito and biting midge control were studied on Parris Island Marine Corps Recruit Depot, Parris Island, SC. Aerial applications were made with C-130 aircraft at dusk in 2003 and in 2005. In 2003, we sampled two locations on Parris Island with Malaise traps before and after spraying, and used Before-After analyses to examine changes in terrestrial insect diversity and abundance. In 2005, we sampled insects with yellow pan traps at three locations on Parris Island and at an untreated control site. A Before-After Control-Impact analysis at each location was conducted to compare changes. In 2003, numbers of four of 12 common taxa (Dolichopodidae, Sarcophagidae, Syrphidae, Tachinidae) were lower after sprays. However, there were no significant changes in numbers of common taxa or total numbers in 2005. Shannon diversities (H') were not different in either year indicating that sprays had minimal impact on overall community biodiversity. In contrast, populations of pestiferous biting midges (Culicoides spp.) collected in CDC-style traps were reduced by 94-99% after spraying in both years; mosquito numbers declined by 88.2% in 2003 and 92.5% in 2005, after sprays. PMID:20388292

  12. Vinclozolin alters the expression of hormonal and stress genes in the midge Chironomus riparius.

    PubMed

    Aquilino, Mónica; Sánchez-Argüello, Paloma; Martínez-Guitarte, José-Luis

    2016-05-01

    Vinclozolin is a fungicide used in agriculture that can reach aquatic ecosystems and affect the organisms living there. Its effects have been intensively studied in vertebrates, where it acts as an antiandrogen, but there is a lack of information about its mechanistic effects on invertebrates. In this work, we analyzed the response of genes related to the endocrine system, the stress response, and the detoxification mechanisms of Chironomus riparius fourth instar larvae after 24h and 48h exposures to 20 (69.9nM), 200 (699nM), and 2000μg/L (6.99μM) of Vinclozolin. Survival analysis showed that this compound has low toxicity, as it was not lethal for this organism at the concentrations used. However, this fungicide was shown to modify the transcriptional activity of the ecdysone response pathway genes EcR, E74, and Kr-h1 by increasing their mRNA levels. While no changes were observed in disembodied, a gene related with the ecdysone synthesis metabolic pathway, Cyp18A1, which is involved in the inactivation of the active form of ecdysone, was upregulated. Additionally, the expression of two genes related to other hormones, FOXO and MAPR, did not show any changes when Vinclozolin was present. The analysis of stress response genes showed significant changes in the mRNA levels of Hsp70, Hsp24, and Gp93, indicating that Vinclozolin activates the cellular stress mechanisms. Finally, the expressions of the genes Cyp4G and GstD3, which encode enzymes involved in phase I and phase II detoxification, respectively, were analyzed. It was found that their mRNA levels were altered by Vinclozolin, suggesting their involvement in the degradation of this compound. For the first time, these results show evidence that Vinclozolin can modulate gene expression, leading to possible significant endocrine alterations of the insect endocrine system. These results also offer new clues about the mode of action of this compound in invertebrates. PMID:26966872

  13. Atypical mechanoreceptors in larvae of biting midges Forcipomyia nigra (Diptera: Ceratopogonidae).

    PubMed

    Urbanek, Aleksandra; Kapusta, Małgorzata

    2016-09-01

    The dorsolateral setae of Forcipomyia nigra have been investigated. They are mechanoreceptors, sensilla trichoidea, innerved by a single neuron. The tubular body is located at the base of the hair shaft. Although the fine structure of the dorsolateral setae is similar to dorsal setae that perform a double function: secretion of a hygroscopic viscous substance through the pores and mechanoreception dorsolateral setae, they do not secrete any fluid. In both types of setae, trichogen cells (hair forming cells) produce the hair shafts and thereafter do not retract from the cavity of the setae. They contain a large polyploid nucleus and expanded bundles of microtubules. In dorsolateral mechanoreceptors, the microtubules form a network around the nucleus of the trichogen cell and are especially numerous in the cytoplasm invading the interior of the seta, which is evidenced by immunofluorescence light microscopy. No tormogen cell, responsible for the production of the setal socket, was found. Our observations indicate that the dorsolateral setae are solely mechanoreceptors but their trichogen cells reveal some glandular activity. PMID:27428285

  14. Effects of bioirrigation of non-biting midges (Diptera: Chironomidae) on lake sediment respiration

    PubMed Central

    Baranov, Viktor; Lewandowski, Jörg; Romeijn, Paul; Singer, Gabriel; Krause, Stefan

    2016-01-01

    Bioirrigation or the transport of fluids into the sediment matrix due to the activities of organisms such as bloodworms (larvae of Diptera, Chironomidae), has substantial impacts on sediment respiration in lakes. However, previous quantifications of bioirrigation impacts of Chironomidae have been limited by technical challenges such as the difficulty to separate faunal and bacterial respiration. This paper describes a novel method based on the bioreactive tracer resazurin for measuring respiration in-situ in non-sealed systems with constant oxygen supply. Applying this new method in microcosm experiments revealed that bioirrigation enhanced sediment respiration by up to 2.5 times. The new method is yielding lower oxygen consumption than previously reported, as it is only sensitive to aerobic heterotrophous respiration and not to other processes causing oxygen decrease. Hence it decouples the quantification of respiration of animals and inorganic oxygen consumption from microbe respiration in sediment. PMID:27256514

  15. Unconventional conservation among genes encoding small secreted salivary sland proteins from a gall midge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to functional constraints associated with protein-coding sequences, introns and the 3’-untranslated region (UTR) of most genes vary the most, followed by the 5’-UTR. The coding region is the most conserved due to stronger functional constraints. During characterization of transcripts and gene...

  16. Polypedilum nubifer, a Chironomid Midge (Diptera: Chironomidae) new to Florida that has nuisance potential

    SciTech Connect

    Jacobsen, R.E.; Perry, S.A.

    2007-03-15

    We document the first record of Polypedilum nubifer in Pan-America. This eurytopic species often reaches severe nuisance population sizes in Australia, Asia, and Hawaii in warm, shallow, eutrophic waters subject to drying. A large population was discovered in newly-constructed infiltration basins and neighboring marshes along the eastern boundary of Everglades National Park. Presently, this population appears minimally invasive to Park marshes and is far removed from urban areas. However, we anticipate this species could disperse and attain nuisance population sizes in suitable urban and agricultural habitats in south Florida. (author)

  17. ACUTE AND CHRONIC EFFECTS OF ALUM TO MIDGE LARVA (DIPTERA: CHIRONOMIDAE)

    EPA Science Inventory

    The use of aluminum sulfate (alum) to precipitate phosphorus in highly eutrophic lakes is increasing. As use increases, the need to study the effects of alum on the biota increases. Possible adverse effects of alum on lake organisms may be due to chemical toxicity from dissolved ...

  18. Slow dehydration promotes desiccation and freeze tolerance in the Antarctic midge Belgica antarctica

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adaptations to low moisture availability are arguably as important as cold resistance for polar terrestrial invertebrates, especially because water, in the form of ice, is biologically inaccessible for much of the year. Desiccation responses under ecologically realistic soil humidity conditions – t...

  19. Studies on the chironomid midges (Diptera, Chironomidae) of the Nansei Islands, southern Japan.

    PubMed

    Sasa, M

    1990-06-01

    The Nansei Islands are located in the subtropical zone of the western Pacific Ocean between Kyushu and Taiwan, and are composed of the two main island groups, the Amami and the Ryukyu Archipelagoes. This area has been known for the presence of a number of indigenous animal species. Prior to the present studies, collections of the chironomids mainly in the urban areas of the three main islands of the Ryukyus were carried out by Sasa and Hasegawa, and a total of 42 species, including 25 new species, were recorded. Additional collections of the chironomids mainly in the mountainous areas of this region were carried out by the present author during 1988 and 1989, and a total of 26 species (including 12 new species) were recorded from Amami Island, and a total of 27 species (including 10 new species) were recorded from the Ryukyu Islands. Eight species among them, including 3 new species, were common to the two archipelagos. PMID:2214255

  20. Potential of synthetic sex pheromone blend for mating disruption of the swede midge, Contarinia nasturtii.

    PubMed

    Samietz, Jörg; Baur, Robert; Hillbur, Ylva

    2012-09-01

    The potential for pheromone-based mating disruption of the Brassica pest Contarinia nasturtii was tested, both in small-scale plots with Brussels sprouts and in commercial-scale fields with either broccoli or cauliflower. Experiments in the small-scale plots used laboratory-reared insects released into a previously uninfested area, whereas large-scale experiments used a high natural population of C. nasturtii. Effectiveness of mating disruption was evaluated by the reduction of male captures in pheromone traps, and by reduction of crop damage caused by C. nasturtii. Dental cotton rolls (small-scale experiment) and polyethylene caps (large-scale experiment), containing 50 μg (2S, 9S)-diacetoxyundecane, 100 μg (2S,10S)-diacetoxyundecane, and 1 μg (2S)-acetoxyundecane, spaced 2 m apart, served as dispensers in the test plots. In both experiments, mean catches of C. nasturtii males in pheromone traps were reduced to near zero in treated plots, with control plots averaging 71 males/trap. In the large-scale experiments, no males were caught in pheromone traps over a period of 41 days after mating disruption was applied; one male was caught from days 42-60. In the small-scale trials, crop damage was reduced by 59 %, compared to the untreated control plot. In the large-scale experiments, damage was reduced on average by 91 %. This study shows successful field application of the mating disruption technique for control of a member of the dipteran family Cecidomyiidae, and demonstrates that pheromone-based mating disruption has potential for management of C. nasturtii populations. PMID:22914960

  1. Effect of an Herbivorous Stem Mining Midge on the growth of hydrilla

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hydrilla (Hydrilla verticillata (L.f.)Royle: Hydrocharitaceae) is one of the worst invasive aquatic weeds in the US, with millions of dollars spent annually to control large infestations in all types of water bodies. A major factor contributing to the invasiveness of hydrilla is its pattern of grow...

  2. Ecotoxicity of bare and coated silver nanoparticles in the aquatic midge, Chironomus riparius.

    PubMed

    Park, Sun-Young; Chung, Jiwoong; Colman, Benjamin P; Matson, Cole W; Kim, Younghun; Lee, Byung-Cheon; Kim, Phil-Je; Choi, Kyunghee; Choi, Jinhee

    2015-09-01

    Although sediment is generally considered to be the major sink for nanomaterials in aquatic environments, few studies have addressed the ecotoxicity of nanomaterials in the presence of sediment. In the present study, the ecotoxicity of silver nanoparticles (AgNPs) with a range of organic coatings was examined in a freshwater sediment-dwelling organism, Chironomus riparius, using acute and chronic ecotoxicity endpoints, including molecular indicators. The toxicity of AgNPs coated with different organic materials, such as polyvinylpyrrolidone, gum arabic, and citrate, to C. riparius was compared with that of bare-AgNPs and AgNO3 (ionic silver). Total silver concentration was also measured to monitor the behavior of the AgNPs in water and sediment and to determine how ion dissolution affects the toxicity of all AgNPs. The coated- and bare-AgNPs caused DNA damage and oxidative stress-related gene expression. In addition, the bare-AgNPs and AgNO3 had a significant effect on development and reproduction. The surface coatings generally mitigated the toxicity of AgNPs to C. riparius, which can be explained by the reduced number of ions released from coated-AgNPs. Citrate-AgNPs caused the most significant alteration at the molecular level, but this did not translate to higher-level effects. Finally, comparing previously conducted studies on AgNP-induced gene expression without sediments, the authors show that the presence of sediment appears to mitigate the toxicity of AgNPs. PMID:25892495

  3. Pyrosequencing reveals the predominance of Pseudomonadaceae in gut microbiome of a Gall Midge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gut microbes are known to play various roles in insects such as digestion of inaccessible nutrients, synthesis of deficient amino acids, and interaction with ecological environments, including host plants. Here, we analyzed the gut microbiome in Hessian fly, a serious pest of wheat. A total of 3,654...

  4. The effects of binary UV filter mixtures on the midge Chironomus riparius.

    PubMed

    Ozáez, Irene; Morcillo, Gloria; Martínez-Guitarte, José-Luis

    2016-06-15

    Organic ultraviolet (UV) filters are used in a wide variety of products, including cosmetics, to prevent damage from UV light in tissues and industrial materials. Their extensive use has raised concerns about potential adverse effects in human health and aquatic ecosystems that accumulate these pollutants. To increase sun radiation protection, UV filters are commonly used in mixtures. Here, we studied the toxicity of binary mixtures of 4-methylbenzylidene camphor (4MBC), octyl-methoxycinnamate (OMC), and benzophenone-3 (BP-3), by evaluating the larval mortality of Chironomus riparius. Also molecular endpoints have been analyzed, including alterations in the expression levels of a gene related with the endocrine system (EcR, ecdysone receptor) and a gene related with the stress response (hsp70, heat shock protein 70). The results showed that the mortality caused by binary mixtures was similar to that observed for each compound alone; however, some differences in LC50 were observed between groups. Gene expression analysis showed that EcR mRNA levels increased in the presence of 0.1mg/L 4MBC but returned to normal levels after exposure to mixtures of 4MBC with 0.1, 1, and 10mg/L of BP-3 or OMC. In contrast, the hsp70 mRNA levels increased after exposure to the combinations tested of 4MBC and BP-3 or OMC mixtures. These data suggest that 4MBC, BP-3, and OMC may have antagonist effects on EcR gene transcription and a synergistic effect on hsp70 gene activation. This is the first experimental study to show the complex patterned effects of UV filter mixtures on invertebrates. The data suggest that the interactions within these chemicals mixtures are complex and show diverse effects on various endpoints. PMID:26971216

  5. Effects of bioirrigation of non-biting midges (Diptera: Chironomidae) on lake sediment respiration.

    PubMed

    Baranov, Viktor; Lewandowski, Jörg; Romeijn, Paul; Singer, Gabriel; Krause, Stefan

    2016-01-01

    Bioirrigation or the transport of fluids into the sediment matrix due to the activities of organisms such as bloodworms (larvae of Diptera, Chironomidae), has substantial impacts on sediment respiration in lakes. However, previous quantifications of bioirrigation impacts of Chironomidae have been limited by technical challenges such as the difficulty to separate faunal and bacterial respiration. This paper describes a novel method based on the bioreactive tracer resazurin for measuring respiration in-situ in non-sealed systems with constant oxygen supply. Applying this new method in microcosm experiments revealed that bioirrigation enhanced sediment respiration by up to 2.5 times. The new method is yielding lower oxygen consumption than previously reported, as it is only sensitive to aerobic heterotrophous respiration and not to other processes causing oxygen decrease. Hence it decouples the quantification of respiration of animals and inorganic oxygen consumption from microbe respiration in sediment. PMID:27256514

  6. New species and records of frog-biting midges from southern Brazil (Diptera: Corethrellidae).

    PubMed

    Amaral, André P; Pinho, Luiz Carlos

    2015-01-01

    Corethrella borkenti sp. n. is described, based on female and male adults, pupae and larvae, collected from tank bromeliads in the Atlantic Forest of southern Brazil. The larva and pupa of C. alticola Lane, 1939 are described for the first time. New distributional records for C. alticola and C. vittata Lane, 1939 extend their distributions to the southern Atlantic Forest. A key to pupae of peruviana group is given. PMID:25947691

  7. Reactive Oxygen Species Are Involved in Plant Defense against a Gall Midge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reactive oxygen species (ROS) play a major role in plant defense against pathogens, but evidence for their role in defense against insects is still preliminary and inconsistent. In this study, we examined the potential role of ROS in defense of wheat and rice against Hessian fly (Mayetiola destruct...

  8. New combinations and changes in the classification of Ceratopogonidae (Diptera, biting midges).

    PubMed

    Borkent, Art

    2015-01-01

    This short article contains some necessary taxonomic changes prior to the publication of a chapter on the Ceratopogonidae by the author for the upcoming Manual of Afrotropical Diptera and spearheaded by Ashley Kirk-Spriggs. Some additional placements of three genera to a recently redefined tribe are also included. PMID:26249516

  9. Developing a preventive immunization approach against insect bite hypersensitivity using recombinant allergens: A pilot study.

    PubMed

    Jonsdottir, Sigridur; Hamza, Eman; Janda, Jozef; Rhyner, Claudio; Meinke, Andreas; Marti, Eliane; Svansson, Vilhjalmur; Torsteinsdottir, Sigurbjorg

    2015-07-15

    Insect bite hypersensitivity (IBH) is an allergic dermatitis of horses caused by bites of midges (Culicoides spp.). IgE-mediated reactions are often involved in the pathogenesis of this disease. IBH does not occur in Iceland due to the absence of Culicoides, but it occurs with a high frequency in Icelandic horses exported to mainland Europe, where Culicoides are present. We hypothesize that immunization with the Culicoides allergens before export could reduce the incidence of IBH in exported Icelandic horses. The aim of the present study was therefore to compare intradermal and intralymphatic vaccination using four purified recombinant allergens, in combination with a Th1 focusing adjuvant. Twelve horses were vaccinated three times with 10μg of each of the four recombinant Culicoides nubeculosus allergens. Six horses were injected intralymphatically, three with and three without IC31(®), and six were injected intradermally, in the presence or absence of IC31(®). Antibody responses were measured by immunoblots and ELISA, potential sensitization in a sulfidoleukotriene release test and an intradermal test, cytokine and FoxP3 expression with real time PCR following in vitro stimulation of PBMC. Immunization with the r-allergens induced a significant increase in levels of r-allergen-specific IgG1, IgG1/3, IgG4/7, IgG5 and IgG(T). Application of the r-allergens in IC31(®) adjuvant resulted in a significantly higher IgG1, IgG1/3, IgG4/7 allergen-specific response. Intralymphatic injection was slightly more efficient than intradermal injection, but the difference did not reach significance. Testing of the blocking activity of the sera from the horses immunized intralymphatically with IC31(®) showed that the generated IgG antibodies were able to partly block binding of serum IgE from an IBH-affected horse to these r-allergens. Furthermore, IgG antibodies bound to protein bands on blots of C. nubeculosus salivary gland extract. No allergen-specific IgE was induced and

  10. Free-living ciliates as potential reservoirs for eukaryotic parasites: occurrence of a trypanosomatid in the macronucleus of Euplotes encysticus

    PubMed Central

    2014-01-01

    Background Flagellates of the family Trypanosomatidae are obligate endoparasites, which can be found in various hosts. Several genera infect insects and occur as monoxenous parasites especially in representatives of Diptera and Hemiptera. These trypanosomatid flagellates probably share the worldwide distribution of their hosts, which are often infested by large numbers of endoparasites. Traditionally, their taxonomy was based on morphology, host origin, and life cycle. Here we report the characterization of a trypanosomatid infection detected in a protozoan, a ciliate collected from a polluted freshwater pond in a suburb of New Delhi (India). Methods Live observations and morphological studies applying light, fluorescence and transmission electron microscopy were conducted. Molecular analyses of host and parasite were performed and used for phylogenetic reconstructions and species (host) or genus level (parasite) identification. Results Although the morphological characteristics were not revealing, a high similarity of the trypanosomatids 18S rRNA gene sequence to Herpetomonas ztiplika and Herpetomonas trimorpha (Kinetoplastida, Trypanosomatidae), both parasites of biting midges (Culicoides kibunensis and Culicoides truncorum, respectively) allowed the assignment to this genus. The majority of the host population displayed a heavy infection that significantly affected the shape of the host macronucleus, which was the main site of parasite localization. In addition, the growth rate of host cultures, identified as Euplotes encysticus according to cell morphology and 18S rRNA gene sequence, was severely impacted by the infection. Conclusions The host-parasite system described here represents a recent example of free-living protists acting as environmental reservoirs for parasitic eukaryotic microorganisms. PMID:24774858

  11. Ecological Drivers of Mansonella perstans Infection in Uganda and Patterns of Co-endemicity with Lymphatic Filariasis and Malaria

    PubMed Central

    Stensgaard, Anna-Sofie; Vounatsou, Penelope; Onapa, Ambrose W.; Utzinger, Jürg; Pedersen, Erling M.; Kristensen, Thomas K.; Simonsen, Paul E.

    2016-01-01

    Background Mansonella perstans is a widespread, but relatively unknown human filarial parasite transmitted by Culicoides biting midges. Although it is found in many parts of sub-Saharan Africa, only few studies have been carried out to deepen the understanding of its ecology, epidemiology, and health consequences. Hence, knowledge about ecological drivers of the vector and parasite distribution, integral to develop spatially explicit models for disease prevention, control, and elimination strategies, is limited. Methodology We analyzed data from a comprehensive nationwide survey of M. perstans infection conducted in 76 schools across Uganda in 2000–2003, to identify environmental drivers. A suite of Bayesian geostatistical regression models was fitted, and the best fitting model based on the deviance information criterion was utilized to predict M. perstans infection risk for all of Uganda. Additionally, we investigated co-infection rates and co-distribution with Wuchereria bancrofti and Plasmodium spp. infections observed at the same survey by mapping geographically overlapping areas. Principal Findings Several bioclimatic factors were significantly associated with M. perstans infection levels. A spatial Bayesian regression model showed the best fit, with diurnal temperature range, normalized difference vegetation index, and cattle densities identified as significant covariates. This model was employed to predict M. perstans infection risk at non-sampled locations. The level of co-infection with W. bancrofti was low (0.3%), due to limited geographic overlap. However, where the two infections did overlap geographically, a positive association was found. Conclusions/Significance This study presents the first geostatistical risk map for M. perstans in Uganda. We confirmed a widespread distribution of M. perstans, and identified important potential drivers of risk. The results provide new insight about the ecologic preferences of this otherwise poorly known filarial

  12. Climate Change Influences on the Global Potential Distribution of Bluetongue Virus.

    PubMed

    Samy, Abdallah M; Peterson, A Townsend

    2016-01-01

    The geographic distribution of arboviruses has received considerable attention after several dramatic emergence events around the world. Bluetongue virus (BTV) is classified among category "A" diseases notifiable to the World Organization of Animal Health (OIE), and is transmitted among ruminants by biting midges of the genus Culicoides. Here, we developed a comprehensive occurrence data set to map the current distribution, estimate the ecological niche, and explore the future potential distribution of BTV globally using ecological niche modeling and based on diverse future climate scenarios from general circulation models (GCMs) for four representative concentration pathways (RCPs). The broad ecological niche and potential geographic distribution of BTV under present-day conditions reflected the disease's current distribution across the world in tropical, subtropical, and temperate regions. All model predictions were significantly better than random expectations. As a further evaluation of model robustness, we compared our model predictions to 331 independent records from most recent outbreaks from the Food and Agriculture Organization Emergency Prevention System for Transboundary Animal and Plant Pests and Diseases Information System (EMPRES-i); all were successfully anticipated by the BTV model. Finally, we tested ecological niche similarity among possible vectors and BTV, and could not reject hypotheses of niche similarity. Under future-climate conditions, the potential distribution of BTV was predicted to broaden, especially in central Africa, United States, and western Russia. PMID:26959424

  13. Bluetongue: a historical and epidemiological perspective with the emphasis on South Africa

    PubMed Central

    2012-01-01

    Bluetongue (BT) is a non-contagious, infectious, arthropod transmitted viral disease of domestic and wild ruminants that is caused by the bluetongue virus (BTV), the prototype member of the Orbivirus genus in the family Reoviridae. Bluetongue was first described in South Africa, where it has probably been endemic in wild ruminants since antiquity. Since its discovery BT has had a major impact on sheep breeders in the country and has therefore been a key focus of research at the Onderstepoort Veterinary Research Institute in Pretoria, South Africa. Several key discoveries were made at this Institute, including the demonstration that the aetiological agent of BT was a dsRNA virus that is transmitted by Culicoides midges and that multiple BTV serotypes circulate in nature. It is currently recognized that BT is endemic throughout most of South Africa and 22 of the 26 known serotypes have been detected in the region. Multiple serotypes circulate each vector season with the occurrence of different serotypes depending largely on herd-immunity. Indigenous sheep breeds, cattle and wild ruminants are frequently infected but rarely demonstrate clinical signs, whereas improved European sheep breeds are most susceptible. The immunization of susceptible sheep remains the most effective and practical control measure against BT. In order to protect sheep against multiple circulating serotypes, three pentavalent attenuated vaccines have been developed. Despite the proven efficacy of these vaccines in protecting sheep against the disease, several disadvantages are associated with their use in the field. PMID:22973992

  14. Generation of Recombinant Modified Vaccinia Virus Ankara Encoding VP2, NS1, and VP7 Proteins of Bluetongue Virus.

    PubMed

    Marín-López, Alejandro; Ortego, Javier

    2016-01-01

    Modified Vaccinia Virus Ankara (MVA) is employed widely as an experimental vaccine vector for its lack of replication in mammalian cells and high expression level of foreign/heterologous genes. Recombinant MVAs (rMVAs) are used as platforms for protein production as well as vectors to generate vaccines against a high number of infectious diseases and other pathologies. The portrait of the virus combines desirable elements such as high-level biological safety, the ability to activate appropriate innate immune mediators upon vaccination, and the capacity to deliver substantial amounts of heterologous antigens. Recombinant MVAs encoding proteins of bluetongue virus (BTV), an Orbivirus that infects domestic and wild ruminants transmitted by biting midges of the Culicoides species, are excellent vaccine candidates against this virus. In this chapter we describe the methods for the generation of rMVAs encoding VP2, NS1, and VP7 proteins of bluetongue virus as a model example for orbiviruses. The protocols included cover the cloning of VP2, NS1, and VP7 BTV-4 genes in a transfer plasmid, the construction of recombinant MVAs, the titration of virus working stocks and the protein expression analysis by immunofluorescence and radiolabeling of rMVA infected cells as well as virus purification. PMID:26458834

  15. Use of high spatial resolution satellite imagery to characterize landscapes at risk for bluetongue.

    PubMed

    Guis, Hélène; Tran, Annelise; de La Rocque, Stéphane; Baldet, Thierry; Gerbier, Guillaume; Barragué, Bruno; Biteau-Coroller, Fabienne; Roger, François; Viel, Jean-François; Mauny, Frédéric

    2007-01-01

    The recent and rapid spread in the Mediterranean Basin of bluetongue, a viral disease of ruminants transmitted by some species of Culicoides (biting midges), highlights the necessity of determining the conditions of its emergence. This study uses high spatial resolution satellite imagery and methods from landscape ecology science to identify environmental parameters related to bluetongue occurrence in Corsica, a French Mediterranean island where the disease occurred for the first time in 2000. A set of environmental variables recorded in the neighborhood of 80 sheep farms were related to case occurrence through a logistic regression model computed within three subsequent buffer distances of 0.5, 1 and 2 km. The results reveal the role of landscape metrics, particularly those characterizing land-use units such as prairies and woodlands, as well as farm type, latitude and sunshine to explain the presence of bluetongue. Internal and external validation both indicate that the best results are obtained with the 1 km buffer size model (area under Receiver Operating Characteristic curve = 0.9 for internal validation and 0.81 for external validation). The results show that high spatial resolution remote sensing (i.e. 10 m pixels) and landscape ecology approaches contribute to improving the understanding of bluetongue epidemiology. PMID:17583664

  16. Schmallenberg disease in sheep or goats: Past, present and future.

    PubMed

    Lievaart-Peterson, K; Luttikholt, S; Peperkamp, K; Van den Brom, R; Vellema, P

    2015-12-14

    Schmallenberg disease has emerged in North-Western Europe in 2011 and has since spread widely, even across the European borders. It has the potency to infect many, mainly ruminant, species, but seems to lack zoonotic potential. Horizontal transmission occurs through various Culicoides biting midges and subsequent trans-placental transmission causes teratogenic effects. In some small ruminants, clinical signs, including fever, decreased milk production and diarrhea occur during the viraemic phase, but infection is mostly asymptomatic. However, fetal Schmallenberg virus infection in naïve ewes and goats can result in stillborn offspring, showing a congenital arthrogryposis-hydranencephaly syndrome. The economic impact of infection depends on the number of malformed lambs, but is generally limited. There is debate on whether Schmallenberg virus has newly emerged or is re-emerging, since it is likely one of the ancestors of Shamonda virus, both Orthobunyaviruses belonging to the species Sathuperi virus within the Simbu serogroup viruses. Depending on the vector-borne transmission and the serologic status, future outbreaks of Schmallenberg disease induced congenital disease are expected. PMID:26441013

  17. Mansonella ozzardi: a neglected New World filarial nematode.

    PubMed

    Lima, Nathália F; Veggiani Aybar, Cecilia A; Dantur Juri, María J; Ferreira, Marcelo U

    2016-05-01

    Mansonella ozzardi (Nematoda: Onchocercidae) is an understudied filarial nematode, originally described by Patrick Manson in 1897, that can be transmitted by two families of dipteran vectors, biting midges (most of them members of the genus Culicoides) and black flies (genus Simulium). With a patchy geographic distribution from southern Mexico to northwestern Argentina, human infection with M. ozzardi is highly prevalent in some of the Caribbean islands, along riverine communities in the Amazon Basin, and on both sides of the border between Bolivia and Argentina. There is no clinical entity unequivocally associated with M. ozzardi infection, although fever, arthralgia, headache, cold lower extremities, and itchy cutaneous rashes are occasionally mentioned in case report series. More recently, ocular manifestations (especially keratitis) have been associated with mansonelliasis, opening an important area of investigation. Here, we briefly review the biology, epidemiology, pathogenesis, and clinical aspects of M. ozzardi infection and point to some existing knowledge gaps, aiming to stimulate a research agenda to help filling them. PMID:27376501

  18. Comparing the effect of modeled climatic variables on the distribution of African horse sickness in South Africa and Namibia.

    PubMed

    Liebenberg, Danica; van Hamburg, Huib; Piketh, Stuart; Burger, Roelof

    2015-12-01

    Africa horse sickness (AHS) is a lethal disease of horses with a seasonal occurrence that is influenced by environmental conditions that favor the development of Culicoides midges (Diptera: Ceratopogonidae). This study compared and evaluated the relationship of various modeled climatic variables with the distribution and abundance of AHS in South Africa and Namibia. A comprehensive literature review of the historical AHS reported data collected from the Windhoek archives as well as annual reports from the Directorate of Veterinary services in Namibia were conducted. South African AHS reported data were collected from the South African Department of Agriculture, Forestry, and Fisheries. Daily climatic data were extracted for the time period 1993-2011 from the ERA-interim re-analysis dataset. The principal component analysis of the complete dataset indicated a significant statistical difference between Namibia and South Africa for the various climate variables and the outbreaks of AHS. The most influential parameters in the distribution of AHS included humidity, precipitation, evaporation, and minimum temperature. In South Africa, temperature had the most significant effect on the outbreaks of AHS, whereas in Namibia, humidity and precipitation were the main drivers. The maximum AHS cases in South Africa occurred at temperatures of 20-22° C and relative humidity between 50-70%. Furthermore, anthropogenic effects must be taken into account when trying to understand the distribution of AHS. PMID:26611969

  19. Climate Change Influences on the Global Potential Distribution of Bluetongue Virus

    PubMed Central

    Samy, Abdallah M.; Peterson, A. Townsend

    2016-01-01

    The geographic distribution of arboviruses has received considerable attention after several dramatic emergence events around the world. Bluetongue virus (BTV) is classified among category “A” diseases notifiable to the World Organization of Animal Health (OIE), and is transmitted among ruminants by biting midges of the genus Culicoides. Here, we developed a comprehensive occurrence data set to map the current distribution, estimate the ecological niche, and explore the future potential distribution of BTV globally using ecological niche modeling and based on diverse future climate scenarios from general circulation models (GCMs) for four representative concentration pathways (RCPs). The broad ecological niche and potential geographic distribution of BTV under present-day conditions reflected the disease’s current distribution across the world in tropical, subtropical, and temperate regions. All model predictions were significantly better than random expectations. As a further evaluation of model robustness, we compared our model predictions to 331 independent records from most recent outbreaks from the Food and Agriculture Organization Emergency Prevention System for Transboundary Animal and Plant Pests and Diseases Information System (EMPRES-i); all were successfully anticipated by the BTV model. Finally, we tested ecological niche similarity among possible vectors and BTV, and could not reject hypotheses of niche similarity. Under future-climate conditions, the potential distribution of BTV was predicted to broaden, especially in central Africa, United States, and western Russia. PMID:26959424

  20. Genomic sequences of Australian bluetongue virus prototype serotypes reveal global relationships and possible routes of entry into Australia.

    PubMed

    Boyle, David B; Bulach, Dieter M; Amos-Ritchie, Rachel; Adams, Mathew M; Walker, Peter J; Weir, Richard

    2012-06-01

    Bluetongue virus (BTV) is transmitted by biting midges (Culicoides spp.). It causes disease mainly in sheep and occasionally in cattle and other species. BTV has spread into northern Europe, causing disease in sheep and cattle. The introduction of new serotypes, changes in vector species, and climate change have contributed to these changes. Ten BTV serotypes have been isolated in Australia without apparent associated disease. Simplified methods for preferential isolation of double-stranded RNA (dsRNA) and template preparation enabled high-throughput sequencing of the 10 genome segments of all Australian BTV prototype serotypes. Phylogenetic analysis reinforced the Western and Eastern topotypes previously characterized but revealed unique features of several Australian BTVs. Many of the Australian BTV genome segments (Seg-) were closely related, clustering together within the Eastern topotypes. A novel Australian topotype for Seg-5 (NS1) was identified, with taxa spread across several serotypes and over time. Seg-1, -2, -3, -4, -6, -7, -9, and -10 of BTV_2_AUS_2008 were most closely related to the cognate segments of viruses from Taiwan and Asia and not other Australian viruses, supporting the conclusion that BTV_2 entered Australia recently. The Australian BTV_15_AUS_1982 prototype was revealed to be unusual among the Australian BTV isolates, with Seg-3 and -8 distantly related to other BTV sequences from all serotypes. PMID:22514341

  1. African horse sickness: The potential for an outbreak in disease-free regions and current disease control and elimination techniques.

    PubMed

    Robin, M; Page, P; Archer, D; Baylis, M

    2016-09-01

    African horse sickness (AHS) is an arboviral disease of equids transmitted by Culicoides biting midges. The virus is endemic in parts of sub-Saharan Africa and official AHS disease-free status can be obtained from the World Organization for Animal Health on fulfilment of a number of criteria. AHS is associated with case fatality rates of up to 95%, making an outbreak among naïve horses both a welfare and economic disaster. The worldwide distributions of similar vector-borne diseases (particularly bluetongue disease of ruminants) are changing rapidly, probably due to a combination of globalisation and climate change. There is extensive evidence that the requisite conditions for an AHS epizootic currently exist in disease-free countries. In particular, although the stringent regulations enforced upon competition horses make them extremely unlikely to redistribute the virus, there are great concerns over the effects of illegal equid movement. An outbreak of AHS in a disease free region would have catastrophic effects on equine welfare and industry, particularly for international events such as the Olympic Games. While many regions have contingency plans in place to manage an outbreak of AHS, further research is urgently required if the equine industry is to avoid or effectively contain an AHS epizootic in disease-free regions. This review describes the key aspects of AHS as a global issue and discusses the evidence supporting concerns that an epizootic may occur in AHS free countries, the planned government responses, and the roles and responsibilities of equine veterinarians. PMID:27292229

  2. African horse sickness.

    PubMed

    Zientara, S; Weyer, C T; Lecollinet, S

    2015-08-01

    African horse sickness (AHS) is a devastating disease of equids caused by an arthropod-borne virus belonging to the Reoviridae family, genus Orbivirus. It is considered a major health threat for horses in endemic areas in sub-Saharan Africa. African horse sickness virus (AHSV) repeatedly caused large epizootics in the Mediterranean region (North Africa and southern Europe in particular) as a result of trade in infected equids. The unexpected emergence of a closely related virus, the bluetongue virus, in northern Europe in 2006 has raised fears about AHSV introduction into Europe, and more specifically into AHSV-free regions that have reported the presence of AHSV vectors, e.g. Culicoides midges. North African and European countries should be prepared to face AHSV incursions in the future, especially since two AHSV serotypes (serotypes 2 and 7) have recently spread northwards to western (e.g. Senegal, Nigeria, Gambia) and eastern Africa (Ethiopia), where historically only serotype 9 had been isolated. The authors review key elements of AHS epidemiology, surveillance and prophylaxis. PMID:26601437

  3. Epizootic haemorrhagic disease.

    PubMed

    Maclachlan, N J; Zientara, S; Savini, G; Daniels, P W

    2015-08-01

    Summary Epizootic haemorrhagic disease (EHD) is an arthropod-transmitted viral disease of certain wild ungulates, notably North American white-tailed deer and, more rarely, cattle. The disease in white-tailed deer results from vascular injury analogous to that caused by bluetongue virus (BTV), to which EHD virus (EHDV) is closely related. There are seven serotypes of EHDV recognised, and Ibaraki virus, which is the cause of sporadic disease outbreaks in cattle in Asia, is included in EHDV serotype 2. The global distribution and epidemiology of BTV and EHDV infections are also similar, as both viruses occur throughout temperate and tropical regions of the world where they are transmitted by biting Culicoides midges and infect a wide variety of domestic and wild ungulates. However, the global distribution and epidemiology of EHDV infection are less well characterised than they are for BTV. Whereas most natural and experimental EHDV infections (other than Ibaraki virus infection) of livestock are subclinical or asymptomatic, outbreaks of EHD have recently been reported among cattle in the Mediterranean Basin, Reunion Island, South Africa, and the United States. Accurate and convenient laboratory tests are increasingly available for the sensitive and specific serological and virological diagnosis of EHDV infection and confirmation of EHD in animals, but commercial vaccines are available only for prevention of Ibaraki disease and not for protection against other strains and serotypes of EHDV. PMID:26601439

  4. Effects of TFM and Bayer 73 on in vivo oxygen consumption of the aquatic midge Chironomus tentans

    USGS Publications Warehouse

    Kawatski, J.A.; Dawson, V.K.; Reuvers, J.L.

    1974-01-01

    Exposure of fourth instar larvae of Chironomus tentans to 2.0-8.0 mg/liter of TFM (3-trifluormethyl-4-nitrophenol) for 6 hr at 22 A? 0.5 C in soft water resulted in a significantly increased rate of larval oxygen consumption compared to that of control larvae, as measured with the Warburg respirometer. Maximum stimulation of oxygen consumption occurred with 8.0 mg/liter of TFM, and 1.0 mg/liter of TFM had no measurable effect on basal respiration. When hardness of exposure water was progressively increased, the effect of TFM on oxygen consumption was diminished. Bayer 73 (5,2'-dichloro-4'-nitrosalicylanilide) stimulated oxygen consumption at 0.75 and 1.0 mg/liter, had no significant effect at concentrations less that 0.75 mg/liter, and inhibited oxygen consumption at concentrations of 1.20 mg/liter or greater. Mixtures of TFM and Bayer 73, in the ratio of 98:2, had no greater effect on oxygen consumption than TFM alone.

  5. Uptake, elimination, and biotransformation of the lampricide 3-trifluoromethyl-4-nitrophenol (TFM) by larvae of the aquatic midge Chironomus tentans.

    PubMed

    Kawatski, J A; Bittner, M A

    1975-05-01

    Accumulation of [14C]3-trifluoromethyl-4-nitrophenol ([14C]TFM) by chironomid larvae from sublethal aqueous concentrations is rapid and dependent on hardness of exposure water. TFM is readily biotransformed to at least two more polar derivatives, including sulfated TFM and TFM-glucuronide or galacturonide. Some TFM is also reduced to the phenol amine. Chironomids can quickly eliminate all TFM derivatives as well as the parent [14C]TFM. PMID:1154422

  6. Fluctuating asymmetry and mentum gaps in populations of the midge Chironomus riparius (Diptera: Chironomidae) from a metal-contaminated River

    SciTech Connect

    Groenendijk, D.; Zeinstra, L.W.M.; Postma, J.F.

    1998-10-01

    The developmental stability of both metal-exposed and nonexposed Chironomus riparius populations from the lowland River Dommel was investigated using fluctuating asymmetry (FA) and the incidence of mentum gaps. It was hypothesized that larval development was affected by the influx of Cd, Zn, Fe, Cu, and Pb directly by chemical stress, as well as through inbreeding of metal-adapted and nonadapted specimens. Morphological para/meters were therefore assessed in field-collected larvae and in clean, laboratory-cultured, first-generation (F1) larvae. Fluctuating asymmetry values and mentum gap incidence at contaminated field sites were significantly higher than at clean, upstream locations. Furthermore, FA values of clean, laboratory-cultured F1 larvae generally fell to reference values, indicating the direct effect of metal pollution on developmental aberrations. Mentum gaps were not observed in clean F1 cultures. Slightly elevated FA values were, however, still observed in clean F1 larvae from polluted locations downstream from the metal input. This residual disturbance was thought to reflect genetic stress emerging from interbreeding between metal-adapted and nonadapted specimens. Fluctuating asymmetry and mentum gaps together serve as a useful ecotoxicological marker for metal stress and, when combined with in situ studies and F1 cultures, allow for analysis of the response of animal populations to spatial and temporal gradients in metal exposure.

  7. The bud midge Prodiplosis longifila: Damage characteristics, potential distribution and presence on a new crop host in Colombia.

    PubMed

    Hernandez, Luis M; Guzman, Yoan C; Martínez-Arias, Adriana; Manzano, Maria R; Selvaraj, John J

    2015-01-01

    The Dipteran Prodiplosis longifila is a severe pest, mainly of Solanaceae, in South America and some years ago it damaged Tahiti lime crops in the United States. It is a potential invasive pest. Despite its presence in Colombia, nothing is known regarding the taxonomic identification of P. longifila or the characteristics of the damage it produces. Moreover, the current and potential distributions of this pest are unknown. To determine these factors, P. longifila was sampled in several Solanaceae- and Citrus (x) latifolia (Tahiti lime)-producing areas in Colombia. The larvae consumed tender foliage, flowers and fruits in tomato, fruits in sweet pepper, and buds in Tahiti lime. P. longifila was not found in asparagus or in potatoes. Its presence in Tahiti lime was previously unknown in Colombia. Adults recovered in the laboratory were taxonomically identified using male morphological characteristics such as the shapes of the genitalia, antenna and wing. P. longifila was found in the Andean region of Colombia. The ecological niche model for populations found in tomato suggests that P. longifila is limited in its distribution by altitude and variables associated with temperature and precipitation. The highest probability of occurrence is in areas where tomato, sweet pepper and the new host, Tahiti lime, are grown. Therefore, it is necessary to implement preventive measures, such as planting tomato materials free of P. longifila larvae, in areas where the pest is not yet present but where there is the potential for its development. PMID:25977894

  8. Survival in extreme environment by "preserve-expand-specialize" strategy: lessons from comparative genomics of an anhydrobiotic midge.

    NASA Astrophysics Data System (ADS)

    Gusev, Oleg; Sugimoto, Manabu; Novikova, Nataliya; Sychev, Vladimir; Okuda, Takashi; Kikawada, Takahiro

    2012-07-01

    Anhydrobiotic chironomid larvae of Polypedilum vanderplanki (Diptera) can withstand prolonged complete desiccation as well as other external stresses including ionizing radiation. Recent experiments showed that this insect is able to survive long-tern exposure to real outer space. At the same time, we found that dehydration causes alterations in chromatin structure and a severe fragmentation of nuclear DNA in the cells of the larvae despite successful anhydrobiosis. Analysis of several remote populations of the chironomid in Africa that desiccation-related DNA damage might be a driving genetic force for rapid radiation within the species. First results of ongoing genome project suggest that origin and evolution of anhydrobiosis in this single insect species related to rapid duplication of the genes, coding late embryogenesis abundant proteins (LEA) and other molecular agents directly involved in desiccation resistance in the cells. Analysis of genome-wide mRNA expression profiles in the larvae subjected to desiccation shows that joint-activity of large multiple-genes coding regions in the genome involved in control of anhydrobiosis-related molecular adaptations in the chironomid.

  9. Support for the evolutionary speed hypothesis from intraspecific population genetic data in the non-biting midge Chironomus riparius.

    PubMed

    Oppold, Ann-Marie; Pedrosa, João A M; Bálint, Miklós; Diogo, João B; Ilkova, Julia; Pestana, João L T; Pfenninger, Markus

    2016-02-24

    The evolutionary speed hypothesis (ESH) proposes a causal mechanism for the latitudinal diversity gradient. The central idea of the ESH is that warmer temperatures lead to shorter generation times and increased mutation rates. On an absolute time scale, both should lead to an acceleration of selection and drift. Based on the ESH, we developed predictions regarding the distribution of intraspecific genetic diversity: populations of ectothermic species with more generations per year owing to warmer ambient temperatures should be more differentiated from each other, accumulate more mutations and show evidence for increased mutation rates compared with populations in colder regions. We used the multivoltine insect species Chironomus riparius to test these predictions with cytochrome oxidase I (COI) sequence data and found that populations from warmer regions are indeed significantly more differentiated and have significantly more derived haplotypes than populations from colder regions. We also found a significant correlation of the annual mean temperature with the population mutation parameter θ that serves as a proxy for the per generation mutation rate under certain assumptions. This pattern could be corroborated with two nuclear loci. Overall, our results support the ESH and indicate that the thermal regime experienced may be crucially driving the evolution of ectotherms and may thus ultimately govern their speciation rate. PMID:26888029

  10. Identification of Anhydrobiosis-related Genes from an Expressed Sequence Tag Database in the Cryptobiotic Midge Polypedilum vanderplanki (Diptera; Chironomidae)*

    PubMed Central

    Cornette, Richard; Kanamori, Yasushi; Watanabe, Masahiko; Nakahara, Yuichi; Gusev, Oleg; Mitsumasu, Kanako; Kadono-Okuda, Keiko; Shimomura, Michihiko; Mita, Kazuei; Kikawada, Takahiro; Okuda, Takashi

    2010-01-01

    Some organisms are able to survive the loss of almost all their body water content, entering a latent state known as anhydrobiosis. The sleeping chironomid (Polypedilum vanderplanki) lives in the semi-arid regions of Africa, and its larvae can survive desiccation in an anhydrobiotic form during the dry season. To unveil the molecular mechanisms of this resistance to desiccation, an anhydrobiosis-related Expressed Sequence Tag (EST) database was obtained from the sequences of three cDNA libraries constructed from P. vanderplanki larvae after 0, 12, and 36 h of desiccation. The database contained 15,056 ESTs distributed into 4,807 UniGene clusters. ESTs were classified according to gene ontology categories, and putative expression patterns were deduced for all clusters on the basis of the number of clones in each library; expression patterns were confirmed by real-time PCR for selected genes. Among up-regulated genes, antioxidants, late embryogenesis abundant (LEA) proteins, and heat shock proteins (Hsps) were identified as important groups for anhydrobiosis. Genes related to trehalose metabolism and various transporters were also strongly induced by desiccation. Those results suggest that the oxidative stress response plays a central role in successful anhydrobiosis. Similarly, protein denaturation and aggregation may be prevented by marked up-regulation of Hsps and the anhydrobiosis-specific LEA proteins. A third major feature is the predicted increase in trehalose synthesis and in the expression of various transporter proteins allowing the distribution of trehalose and other solutes to all tissues. PMID:20833722

  11. Unbalanced activation of glutathione metabolic pathways suggests potential involvement in plant defense against the gall midge mayetiola destructor in wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Glutathione, a thiol tripeptide of '-glutamylcysteinylglycine, exists abundantly in nearly all organisms. Glutathione participates in various physiological processes involved in redox reactions by serving as an electron donor/acceptor. In this study, we found that the abundance of total glutathion...

  12. Two new species of predatory biting midges of the genus Alluaudomyia from Europe and the Canary Islands (Diptera: Ceratopogonidae).

    PubMed

    Szadziewski, Ryszard; Dominiak, Patrycja; Filatov, Serhii

    2015-01-01

    Alluaudomyia canariensis Szadziewski & Dominiak sp. nov. from the Canary Islands and A. wyskokensis Szadziewski & Dominiak sp. nov. from Poland and Ukraine are described and illustrated. The genus Alluaudomyia is reported from the Canary Islands for the first time. The article is supplemented with a checklist and an identification key for the species so far recorded from Europe and the Canary Islands. PMID:26624483

  13. Identification and reassessment of the specific status of some tropical freshwater midges (Diptera: Chironomidae) using DNA barcode data.

    PubMed

    Pramual, Pairot; Simwisat, Kusumart; Martin, Jon

    2016-01-01

    Chironomidae are a highly diverse group of insects. Members of this family are often included in programs monitoring the health of freshwater ecosystems. However, a difficulty in morphological identification, particularly of larval stages is the major obstacle to this application. In this study, we tested the efficiency of mitochondrial cytochrome c oxidase I (COI) sequences as the DNA barcoding region for species identification of Chironomidae in Thailand. The results revealed 14 species with a high success rate (>90%) for the correct species identification, which suggests the potential usefulness of the technique. However, some morphological species possess high (>3%) intraspecific genetic divergence that suggests these species could be species complexes and need further morphological or cytological examination. Sequence-based species delimitation analyses indicated that most specimens identified as Chironomus kiiensis, Tokunaga 1936, in Japan are conspecific with C. striatipennis, Kieffer 1912, although a small number form a separate cluster. A review of the descriptions of Kiefferulus tainanus (Kieffer 1912) and its junior synonym, K. biroi (Kieffer 1918), following our results, suggests that this synonymy is probably not correct and that K. tainanus occurs in Japan, China and Singapore, while K. biroi occurs in India and Thailand. Our results therefore revealed the usefulness of DNA barcoding for correct species identification of Chironomidae, particularly the immature stages. In addition, DNA barcodes could also uncover hidden diversity that can guide further taxonomic study, and offer a more efficient way to identify species than morphological analysis where large numbers of specimens are involved, provided the identifications of DNA barcodes in the databases are correct. Our studies indicate that this is not the case, and we identify cases of misidentifications for C. flaviplumus, Tokunaga 1940 and K. tainanus. PMID:27395909

  14. Cryptic species in the nuisance midge Polypedilum nubifer (Skuse (Diptera: Chironomidae) and the status of Tripedilum Kieffer.

    PubMed

    Cranston, Peter S; Martin, Jon; Spies, Martin

    2016-01-01

    Polypedilum nubifer (Skuse, 1889), originally described from Australia, is an apparently widespread species of Chironomidae (Diptera) that can attain nuisance densities in some eutrophic water bodies. Appropriate management depends upon the identity and ability to distinguish from potential cryptic taxa. A morphological study of larvae, pupae and adults of both sexes confirmed P. nubifer as widely distributed and frequently abundant, but also revealed two previously cryptic species of limited distribution in northern Australia. These species are described as new and illustrated in all stages here. Polypedilum quasinubifer Cranston sp. n. is described from north-west Queensland, Australia and also from Thailand and Singapore. Polypedilum paranubifer Cranston sp. n. is known only from retention ponds of a uranium mine in Northern Territory, Australia. Unusual morphological features of P. nubifer including alternate Lauterborn organs on the larval antenna, cephalic tubules on the pupa and frontal tubercles on the adult head are present in both new species as well. Newly slide-mounted types of Polypedilum pelostolum Kieffer, 1912 (lectotype designated here) confirm synonymy to Chironomus nubifer Skuse, 1889, examined also as newly-slide mounted types. Reviewed plus new evidence does not support recognition of Tripedilum Kieffer, 1921 as a separate taxon; therefore, Tripedilum is returned to junior synonymy with Polypedilum s. str. PMID:27394199

  15. Nonselective oviposition by a fastidious insect: the laboratory host range of the melaleuca gall midge Lophodiplosis trifida (Diptera: Cecidomyiidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Invasion by the Australian paperbark, Melaleuca quinquenervia, has degraded large expanses of south Florida wetlands. Restoration of these wetlands requires the removal of expansive monocultures of this large tree while simultaneously curtailing its spread. Management strategies developed by feder...

  16. Bluetongue Virus Nonstructural Protein NS3/NS3a Is Not Essential for Virus Replication

    PubMed Central

    van Gennip, René G. P.; van de Water, Sandra G. P.; van Rijn, Piet A.

    2014-01-01

    Orbiviruses form the largest genus of the family Reoviridae consisting of at least 23 different virus species. One of these is the bluetongue virus (BTV) and causes severe hemorrhagic disease in ruminants, and is transmitted by bites of Culicoides midges. BTV is a non-enveloped virus which is released from infected cells by cell lysis and/or a unique budding process induced by nonstructural protein NS3/NS3a encoded by genome segment 10 (Seg-10). Presence of both NS3 and NS3a is highly conserved in Culicoides borne orbiviruses which is suggesting an essential role in virus replication. We used reverse genetics to generate BTV mutants to study the function of NS3/NS3a in virus replication. Initially, BTV with small insertions in Seg-10 showed no CPE but after several passages these BTV mutants reverted to CPE phenotype comparable to wtBTV, and NS3/NS3a expression returned by repair of the ORF. These results show that there is a strong selection for functional NS3/NS3a. To abolish NS3 and/or NS3a expression, Seg-10 with one or two mutated start codons (mutAUG1, mutAUG2 and mutAUG1+2) were used to generate BTV mutants. Surprisingly, all three BTV mutants were generated and the respective AUGMet→GCCAla mutations were maintained. The lack of expression of NS3, NS3a, or both proteins was confirmed by westernblot analysis and immunostaining of infected cells with NS3/NS3a Mabs. Growth of mutAUG1 and mutAUG1+2 virus in BSR cells was retarded in both insect and mammalian cells, and particularly virus release from insect cells was strongly reduced. Our findings now enable research on the role of RNA sequences of Seg-10 independent of known gene products, and on the function of NS3/NS3a proteins in both types of cells as well as in the host and insect vector. PMID:24465709

  17. Quantitative Risk Assessment for African Horse Sickness in Live Horses Exported from South Africa

    PubMed Central

    Sergeant, Evan S.

    2016-01-01

    African horse sickness (AHS) is a severe, often fatal, arbovirus infection of horses, transmitted by Culicoides spp. midges. AHS occurs in most of sub-Saharan Africa and is a significant impediment to export of live horses from infected countries, such as South Africa. A stochastic risk model was developed to estimate the probability of exporting an undetected AHS-infected horse through a vector protected pre-export quarantine facility, in accordance with OIE recommendations for trade from an infected country. The model also allows for additional risk management measures, including multiple PCR tests prior to and during pre-export quarantine and optionally during post-arrival quarantine, as well as for comparison of risk associated with exports from a demonstrated low-risk area for AHS and an area where AHS is endemic. If 1 million horses were exported from the low-risk area with no post-arrival quarantine we estimate the median number of infected horses to be 5.4 (95% prediction interval 0.5 to 41). This equates to an annual probability of 0.0016 (95% PI: 0.00015 to 0.012) assuming 300 horses exported per year. An additional PCR test while in vector-protected post-arrival quarantine reduced these probabilities by approximately 12-fold. Probabilities for horses exported from an area where AHS is endemic were approximately 15 to 17 times higher than for horses exported from the low-risk area under comparable scenarios. The probability of undetected AHS infection in horses exported from an infected country can be minimised by appropriate risk management measures. The final choice of risk management measures depends on the level of risk acceptable to the importing country. PMID:26986002

  18. Quantitative Risk Assessment for African Horse Sickness in Live Horses Exported from South Africa.

    PubMed

    Sergeant, Evan S; Grewar, John D; Weyer, Camilla T; Guthrie, Alan J

    2016-01-01

    African horse sickness (AHS) is a severe, often fatal, arbovirus infection of horses, transmitted by Culicoides spp. midges. AHS occurs in most of sub-Saharan Africa and is a significant impediment to export of live horses from infected countries, such as South Africa. A stochastic risk model was developed to estimate the probability of exporting an undetected AHS-infected horse through a vector protected pre-export quarantine facility, in accordance with OIE recommendations for trade from an infected country. The model also allows for additional risk management measures, including multiple PCR tests prior to and during pre-export quarantine and optionally during post-arrival quarantine, as well as for comparison of risk associated with exports from a demonstrated low-risk area for AHS and an area where AHS is endemic. If 1 million horses were exported from the low-risk area with no post-arrival quarantine we estimate the median number of infected horses to be 5.4 (95% prediction interval 0.5 to 41). This equates to an annual probability of 0.0016 (95% PI: 0.00015 to 0.012) assuming 300 horses exported per year. An additional PCR test while in vector-protected post-arrival quarantine reduced these probabilities by approximately 12-fold. Probabilities for horses exported from an area where AHS is endemic were approximately 15 to 17 times higher than for horses exported from the low-risk area under comparable scenarios. The probability of undetected AHS infection in horses exported from an infected country can be minimised by appropriate risk management measures. The final choice of risk management measures depends on the level of risk acceptable to the importing country. PMID:26986002

  19. Generation of virus like particles for epizootic hemorrhagic disease virus.

    PubMed

    Forzan, Mario; Maan, Sushila; Mazzei, Maurizio; Belaganahalli, Manjunatha N; Bonuccelli, Lucia; Calamari, Monica; Carrozza, Maria Luisa; Cappello, Valentina; Di Luca, Mariagrazia; Bandecchi, Patrizia; Mertens, Peter P C; Tolari, Francesco

    2016-08-01

    Epizootic hemorrhagic disease virus (EHDV) is a distinct species within the genus Orbivirus, within the family Reoviridae. The epizootic hemorrhagic disease virus genome comprises ten segments of linear, double stranded (ds) RNA, which are packaged within each virus particle. The EHDV virion has a three layered capsid-structure, generated by four major viral proteins: VP2 and VP5 (outer capsid layer); VP7 (intermediate, core-surface layer) and VP3 (innermost, sub-core layer). Although EHDV infects cattle sporadically, several outbreaks have recently occurred in this species in five Mediterranean countries, indicating a potential threat to the European cattle industry. EHDV is transmitted by biting midges of the genus Culicoides, which can travel long distances through wind-born movements (particularly over water), increasing the potential for viral spread in new areas/countries. Expression systems to generate self-assembled virus like particles (VLPs) by simultaneous expression of the major capsid-proteins, have been established for several viruses (including bluetongue virus). This study has developed expression systems for production of EHDV VLPs, for use as non-infectious antigens in both vaccinology and serology studies, avoiding the risk of genetic reassortment between vaccine and field strains and facilitating large scale antigen production. Genes encoding the four major-capsid proteins of a field strain of EHDV-6, were isolated and cloned into transfer vectors, to generate two recombinant baculoviruses. The expression of these viral genes was assessed in insect cells by monitoring the presence of specific viral mRNAs and by western blotting. Electron microscopy studies confirmed the formation and purification of assembled VLPs. PMID:27473984

  20. Genome-Wide Association Study of Insect Bite Hypersensitivity in Swedish-Born Icelandic Horses.

    PubMed

    Shrestha, Merina; Eriksson, Susanne; Schurink, Anouk; Andersson, Lisa S; Sundquist, Marie; Frey, Rebecka; Broström, Hans; Bergström, Tomas; Ducro, Bart; Lindgren, Gabriella

    2015-01-01

    Insect bite hypersensitivity (IBH) is the most common allergic skin disease in horses and is caused by biting midges, mainly of the genus Culicoides. The disease predominantly comprises a type I hypersensitivity reaction, causing severe itching and discomfort that reduce the welfare and commercial value of the horse. It is a multifactorial disorder influenced by both genetic and environmental factors, with heritability ranging from 0.16 to 0.27 in various horse breeds. The worldwide prevalence in different horse breeds ranges from 3% to 60%; it is more than 50% in Icelandic horses exported to the European continent and approximately 8% in Swedish-born Icelandic horses. To minimize the influence of environmental effects, we analyzed Swedish-born Icelandic horses to identify genomic regions that regulate susceptibility to IBH. We performed a genome-wide association (GWA) study on 104 affected and 105 unaffected Icelandic horses genotyped using Illumina® EquineSNP50 Genotyping BeadChip. Quality control and population stratification analyses were performed with the GenABEL package in R (λ = 0.81). The association analysis was performed using the Bayesian variable selection method, Bayes C, implemented in GenSel software. The highest percentage of genetic variance was explained by the windows on X chromosomes (0.51% and 0.36% by 73 and 74 mb), 17 (0.34% by 77 mb), and 18 (0.34% by 26 mb). Overlapping regions with previous GWA studies were observed on chromosomes 7, 9, and 17. The windows identified in our study on chromosomes 7, 10, and 17 harbored immune system genes and are priorities for further investigation. PMID:26026046

  1. Haemosporidian infections in the Tengmalm's Owl (Aegolius funereus) and potential insect vectors of their transmission.

    PubMed

    Synek, Petr; Popelková, Alena; Koubínová, Darina; Šťastný, Karel; Langrová, Iva; Votýpka, Jan; Munclinger, Pavel

    2016-01-01

    Sedentary bird species are suitable model hosts for identifying potential vectors of avian blood parasites. We studied haemosporidian infections in the Tengmalm's Owl (Aegolius funereus) in the Ore Mountains of the Czech Republic using molecular detection methods. Sex of owl nestlings was scored using molecular sexing based on fragment analysis of PCR-amplified CHD1 introns. Observed infection prevalences in nestlings and adult owls were 51 and 86 %, respectively. Five parasite lineages were detected. Most of the infections comprised the Leucocytozoon AEFUN02 and STOCC06 lineages that probably refer to distinct Leucocytozoon species. Other lineages were detected only sporadically. Mixed infections were found in 49 % of samples. The main factor affecting the probability of infection was host age. No effect of individual sex on infection probability was evidenced. The youngest infected nestling was 12 days old. High parasite prevalence in the Tengmalm's Owl nestlings suggests that insect vectors must enter nest boxes to transmit parasites before fledging. Hence, we placed sticky insect traps into modified nest boxes, collected potential insect vectors, and examined them for the presence of haemosporidian parasites using molecular detection. We trapped 201 insects which were determined as biting midges from the Culicoides genus and two black fly species, Simulium (Nevermannia) vernum and Simulium (Eusimulium) angustipes. Six haemosporidian lineages were detected in the potential insect vectors, among which the Leucocytozoon lineage BT2 was common to the Tengmalm's Owl and the trapped insects. However, we have not detected the most frequently encountered Tengmalm's Owl Leucocytozoon lineages AEFUN02 and STOCC06 in insects. PMID:26365667

  2. History of Orbivirus research in South Africa.

    PubMed

    Verwoerd, Daniel W

    2012-01-01

    In the early colonial history of South Africa, horses played an important role, both in general transportation and in military operations. Frequent epidemics of African horsesickness (AHS) in the 18th century therefore severely affected the economy. The first scientific research on the disease was carried out by Alexander Edington (1892), the first government bacteriologist of the Cape Colony, who resolved the existing confusion that reigned and established its identity as a separate disease. Bluetongue (BT) was described for the first time by Duncan Hutcheon in 1880, although it was probably always endemic in wild ruminants and only became a problem when highly susceptible Merino sheep were introduced to the Cape in the late 18th century. The filterability of the AHS virus (AHSV) was demonstrated in 1900 by M'Fadyean in London, and that of the BT virus (BTV) in 1905 by Theiler at Onderstepoort, thus proving the viral nature of both agents. Theiler developed the first vaccines for both diseases at Onderstepoort. Both vaccines consisted of infective blood followed by hyper-immune serum, and were used for many years. Subsequent breakthroughs include the adaptation to propagation and attenuation in embryonated eggs in the case of BTV and in mouse brains for AHSV. This was followed by the discovery of multiple serotypes of both viruses, the transmission of both by Culicoides midges and their eventual replication in cell cultures. Molecular studies led to the discovery of the segmented double-stranded RNA genomes, thus proving their genetic relationship and leading to their classification in a genus called Orbivirus. Further work included the molecular cloning of the genes of all the serotypes of both viruses and clarification of their relationship to the viral proteins, which led to much improved diagnostic techniques and eventually to the development of a recombinant vaccine, which unfortunately has so far been unsuitable for mass production. PMID:23327123

  3. Testing of UK Populations of Culex pipiens L. for Schmallenberg Virus Vector Competence and Their Colonization

    PubMed Central

    Manley, Robyn; Harrup, Lara E.; Veronesi, Eva; Stubbins, Francesca; Stoner, Jo; Gubbins, Simon; Wilson, Anthony; Batten, Carrie; Koenraadt, Constantianus J. M.; Henstock, Mark; Barber, James; Carpenter, Simon

    2015-01-01

    Background Schmallenberg virus (SBV), an arboviral pathogen of ruminants, emerged in northern Europe during 2011 and has subsequently spread across a vast geographic area. While Culicoides biting midges (Diptera: Ceratopogonidae) have been identified as a biological transmission agent of SBV, the role of mosquitoes (Diptera: Culicidae) as potential vectors has not been defined beyond small-scale field collections in affected areas. Culex pipiens L. are one of the most widespread mosquitoes in northern Europe; they are present on farms across the region and have previously been implicated as vectors of several other arboviruses. We assessed the ability of three colony lines of Cx. pipiens, originating from geographically diverse field populations, to become fully infected by SBV using semi-quantitative real-time RT-PCR (sqPCR). Findings Two colony lines of Cx. pipiens were created in the UK (‘Brookwood’ and ‘Caldbeck’) from field collections of larvae and pupae and characterised using genetic markers. A third strain of Cx. pipiens from CVI Wageningen, The Netherlands, was also screened during experiments. Intrathoracic inoculation of the Brookwood line resulted in infections after 14 days that were characterised by high levels of RNA throughout individuals, but which demonstrated indirect evidence of salivary gland barriers. Feeding of 322 individuals across the three colony lines on a membrane based infection system resulted in no evidence of full dissemination of SBV, although infections did occur in a small proportion of Cx. pipiens from each line. Conclusions/Significance This study established two novel lines of Cx. pipiens mosquitoes of UK origin in the laboratory and subsequently tested their competence for SBV. Schmallenberg virus replication and dissemination was restricted, demonstrating that Cx. pipiens is unlikely to be an epidemiologically important vector of the virus in northern Europe. PMID:26291533

  4. European Bluetongue Serotype 8: Disease Threat Assessment for U.S. Sheep.

    PubMed

    Drolet, Barbara S; Reister-Hendricks, Lindsey M; Podell, Brendan K; Breitenbach, Jonathan E; McVey, D Scott; van Rijn, Piet A; Bowen, Richard A

    2016-06-01

    Bluetongue virus (BTV) is an orbivirus transmitted by biting midges (Culicoides spp.) that can result in moderate to high morbidity and mortality primarily in sheep and white-tailed deer. Although only 5 serotypes of BTV are considered endemic to the United States, as many as 11 incursive serotypes have been detected in livestock and wildlife in the past 16 years. Introductions of serotypes, with unknown virulence and disease risk, are constant threats to US agriculture. One potential incursive serotype of particular concern is the European strain of BTV-8, which was introduced into Northern Europe in 2006 and caused unprecedented livestock disease and mortality during the 2006-2007 vector seasons. To assess disease risk of BTV-8 in a common white-faced American sheep breed, eight Polled Dorset yearlings were experimentally infected and monitored for clinical signs. Viremia and viral tissue distribution were detected and quantified by real-time qRT-PCR. Overall, clinical disease was moderate with no mortality. Viremia reached as high as 9.7 log10 particles/mL and persisted at 5 logs or higher through the end of the study (28 days). Virus distribution in tissues was extensive with the highest mean titers at the peak of viremia (day 8) in the kidney (8.38 log10 particles/mg) and pancreas (8.37 log10 particles/mg). Virus persisted in tissues of some sheep at 8 logs or higher by day 28. Results of this study suggest that should BTV-8 emerge in the United States, clinical disease in this common sheep breed would likely be similar in form, duration, and severity to what is typically observed in severe outbreaks of endemic serotypes, not the extraordinary disease levels seen in Northern Europe. In addition, a majority of exposed sheep would be expected to survive and act as significant BTV-8 reservoirs with high titer viremias for subsequent transmission to other livestock and wildlife populations. PMID:27111674

  5. Using artificial streams to assess the effects of metal-mining effluent on the life cycle of the freshwater midge (Chironomus tentans) in situ.

    PubMed

    Hruska, Kimberly A; Dubé, Monique G

    2004-11-01

    In 2002, we developed an in situ life-cycle bioassay with Chironomus tentans in artificial streams to evaluate the effects of a complex metal mine effluent under ambient environmental conditions. The bioassay was tested in the field using effluent from the Copper Cliff Waste Water Treatment Plant at INCO (Sudbury, ON, Canada). Chironomus tentans were exposed throughout the life cycle to 45% Copper Cliff effluent, which is the average effluent concentration measured in Junction Creek (ON, Canada), the natural receiving environment. Chironomus tentans in the effluent treatment exhibited reduced survival (p = 0.001), reduced total emergence (p = 0.001), increased time-to-emergence (p = 0.001), and reduced hatching success (p = 0.001) relative to animals in the reference water treatment. Chironomus tentans in the effluent treatment were not significantly different from the reference in terms of growth, sex ratio, number of egg cases/female, and number of eggs/egg case. This research showed how a life-cycle bioassay could be used in situ to assess metal mine effluent effects on a benthic invertebrate. PMID:15559287

  6. Effects of clay minerals and organic matter in formulated sediments on the bioavailability of sediment-associated uranium to the freshwater midge, Chironomus dilutus.

    PubMed

    Crawford, Sarah E; Liber, Karsten

    2015-11-01

    It is well established that bioavailability influences metal toxicity in aquatic ecosystems. However, the factors and mechanisms that influence uranium (U) bioavailability and toxicity in sediment have not been thoroughly evaluated, despite evidence that suggests different sediment components can influence the sorption and interaction of some metals. Given that dissolved U is generally accepted as being the primary bioavailable fraction of U, it is hypothesized that adsorption and interaction of U with different sediment components will influence the bioavailability of U in sediment. We investigated the effects of key sediment physicochemical properties on the bioavailability of U to a model freshwater benthic invertebrate, Chironomus dilutus. Several 10-day spiked sediment bioaccumulation experiments were performed, exposing C. dilutus larvae to a variety of formulated sediments spiked with different concentrations of U (5, 50 and/or 200 mg U/kg d.w.). Mean accumulation of U in C. dilutus larvae decreased significantly from 1195 to 10 mg U/kg d.w. as kaolin clay content increased from 0% to 60% in sediment spiked with 50 mg U/kg d.w. Similarly, higher organic matter content also resulted in a significant reduction of U bioaccumulation in C. dilutus larvae, indicating a reduction in U bioavailability. Concentrations of U in both the overlying water and sediment pore water displayed a strong positive relationship to U bioaccumulation in C. dilutus larvae (r(2) = 0.77, p<0.001 and r(2) = 0.57, p < 0.001, respectively) for all experiments, while total U concentrations in the sediment had a poor relationship to U bioaccumulation (r(2) = 0.10, p = 0.028). Results from this research confirm that sediment clay and organic matter content play a significant role in altering U bioavailability, which is important in informing risk assessments of U contaminated sites and in the development of site-specific sediment quality guidelines for U. PMID:26205073

  7. Description of a new species of Aphanogmus Thomson (Hymenoptera, Ceraphronidae) that parasitizes acarivorous gall midges of Feltiella (Diptera, Cecidomyiidae) in Japan

    PubMed Central

    Matsuo, Kazunori; Ganaha-Kikumura, Tomoko; Ohno, Suguru; Yukawa, Junichi

    2016-01-01

    Abstract In 2008–2009, we reared small ceraphronids (about 0.5 mm in body length) from cocoons that had been made possibly by two acarivorous species, Feltiella acarisuga (Vallot) and Feltiella acarivora (Zehntner) (Diptera: Cecidomyiidae) in Okinawa, Japan. Detailed morphological observation revealed that the ceraphronid was a new species of Aphanogmus Thomson (Hymenoptera: Ceraphronidae). We describe it as Aphanogmus flavigastris Matsuo, sp. n. Identification of the Aphanogmus species is essential to evaluate its possibly negative effects on the predatory activity of Feltiella species that have been used as control agents against tetranychid mites. PMID:27408578

  8. Who Cares if Barbie Loves Midge, as Long as They Get the Dreamhouse?: Poor and Working Class Lesbians of the New Millennium.

    ERIC Educational Resources Information Center

    Carter, Julie Hope

    1998-01-01

    In-depth interviews with 10 working-class lesbians, aged 16-22, examined how they envisioned their lives, their experiences related to sexual orientation growing up and in school, meanings and consequences of being poor and working class, and additional difficulties for minority-group lesbians. Most interviewees had goals of partaking in the…

  9. Resistance of Sunflower Germplasm to the Sunflower Stem Weevil and Red Sunflower Seed Weevil and Evaluation of Commercial Hybrids for Resistance to the Sunflower Midge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the central and northern Plains, cultivated sunflower (Helianthus annuus L.) is attacked by a number of insect pests resulting in yield losses for sunflower producers. Host-plant resistance can provide a long-term solution to managing these insects with reduced input costs and with potentially lo...

  10. The pupae of the biting midges of the world (Diptera: Ceratopogonidae), with a generic key and analysis of the phylogenetic relationships between genera.

    PubMed

    Borkent, Art

    2014-01-01

    The pupae of species in each of the 45 genera of Ceratopogonidae known in this stage are diagnosed and described. A standard set of terms is provided, with a glossary, for all pertinent structures of the pupal stage within a context of other Culicomorpha. The variety of terms provided by previous authors are synonymized. Some pupal structures are directly related to developing adult structures and these are discussed. A key to the genera (and to the subgenera of Forcipomyia Meigen) allows for their identification. Pupation and pupal behaviour is summarized. A table of all previous descriptions of each stage of the immatures (egg, larva, pupa) is provided, showing that 13% of all validly named extant Ceratopogonidae are known as pupae. This study examined 45% of these species. All species known as fossil pupae are discussed. A phylogenetic analysis based primarily on pupal characters confirms the relationships between the subfamilies as well as the relationships between the genera in Leptoconopinae, Forcipomyiinae and Dasyheleinae. The question of the monophyly of the Culicoidini remains unresolved. Results confirm the paraphyly of the Ceratopogonini and, for the first time, the Sphaeromiini sensu lato, which is divided into Hebetulini (new tribe), Johannsenomyiini Crampton (new status) and Sphaeromiini sensu novum. Sphaeromiini sensu novum includes Sphaeromias Curtis, Leehelea Debenham, Homohelea Kieffer and Xenohelea Kieffer and forms the sister group of the Palpomyiini. Other genera in Sphaeromiini sensu lato not known as pupae are discussed. The genus Mallochohelea Wirth is shown to be polyphyletic and one group of species is therefore recognized as members of the new genus Anebomyia (type species = Mallochohelea atripes Wirth). A number of species previously placed in Stilobezzia Kieffer are shown to belong to Schizonyxhelea Clastrier. Study of the type species of the monotypic genus Nemoromyia Liu and Yu showed it to be a member of the Palpomyia distincta species group and the generic name is therefore a new junior synonym of Palpomyia. Examination of pupae showed that the following species were misplaced and are now in other genera as follows: Schizonyxhelea brevicostalis (Das Gupta & Wirth), 1968: 28 (Stilobezzia) new combination, Schizonyxhelea bulla (Thomsen), 1935: 289 (Stilobezzia) new combination, Schizonyxhelea caribe (Lane & Forattini), 1958: 208 (Stilobezzia) new combination, Schizonyxhelea diminuta (Lane & Forattini), 1958: 209 (Stilobezzia) new combination, Schizonyxhelea obscura (Lane & Forattini), 1958: 216 (Stilobezzia) new combination, Schizonyxhelea panamensis (Lane & Forattini), 1958: 218 (Stilobezzia) new combination, Schizonyxhelea thomsenae (Wirth), 1953: 83 (Stilobezzia) new combination, Schizonyxhelea scutata (Lane & Forattini), 1961: 92 (Stilobezzia) new combination, Pellucidomyia geari (de Meillon & Wirth), 1981: 547 (Macropeza) new combination, Dibezzia prominens (Johannsen) 1932: 435 (Johannsenomyia) new combination, Nilobezzia theileri (de Meillon & Wirth, 1981:552) (Sphaeromias) new combination, Anebomyia atripes (Wirth, 1962: 281) (Mallochohelea) new combination, Anebomyia fluminea (de Meillon & Wirth), 1981: 550 (Mallochohelea) new combination, Anebomyia siricis (de Meillon), 1961: 50 (Sphaeromias) new combination, Anebomyia texensis (Wirth), 1962: 283 (Mallochohelea) new combination, Anebomyia yunnana (Yu & Zou), in Yu et al. 2005: 1503 (Mallochohelea) new combination, Bezzia goezii (Schrank), 1803: 72 (Tipula) new combination (also a nomen nudum), Palpomyia nemorosa (Liu & Yu), 1991: 26 (Nemoromyia) new combination. Bezzia xanthogaster (Kieffer), 1919: 130 (Probezzia) is a junior homonym of Probezzia xanthogaster (Kieffer), 1917: 329 (Bezzia) and is here given the new name Bezzia gilvigaster Borkent. The fossil genus Paraculicoides Pierce, 1966: 94 and its type species Paraculicoides rouseae Pierce, 1966: 94 are removed from the Ceratopogonidae and likely belong in the Psychodidae. PMID:25544570

  11. [Inversion polymorphism of the nonbiting midges Camptochironomus pallidivittatus Edwards, 1929 (Diptera, Chironomidae) from populations of the Lower Volga region and Central Caucasus].

    PubMed

    Polukonova, N V; Karmokov, M Kh; Shaternikov, A N

    2015-02-01

    The karyotype of Camptochironomus pallidivittatus Edwards, 1929 (Diptera, Chironomidae) from five populations of the Lower Volga region and Central Caucasus (the northern macroslope) has been studied. In populations of S. pallidivittatus from the Central Caucasus, 11 banding sequences (BS) were found; one sequence, pal B10, was new to the species. In the Saratov population, 11 BS were also found, three of which were new for the species-pal A3, pal B11, and pal B12. The banding sequences detected for the first time have not yet been found in other parts of the habitat of this species and may be endemic to these regions. In the studied populations ofS. pallidivittatus, banding sequences were found that were nonstandard but fixed in the karyotype. This is indicative of some degree of chromosomal divergence. These banding sequences include pal A2.2 in arm A and pal B10.10 in arm B in the Central Caucasus region, as well as pal B2.2 and pal G2.2 in the Lower Volga region. Arms A, B, D, and G in the Central Caucasian populations and A, B, and D in the Saratov oblast were polymorphic. The composition of heterozygous sequences between populations from different regions coincided only in arm D (pal D 1.2). In arms A and B, the set of heterozygous BS was different: pal A1.2 and pal B1.10 sequences were found in the Central Caucasian populations, and pal A1.3 and B11.12 were found in Saratov oblast. The number of genotypic combinations of S. pallidivittatus was higher in the Central Caucasus region, whereas the number of zygotic combinations was higher in the Saratov population. The percentage of heterozygous larvae in the Central Caucasian populations varied from 20 to 80, whereas all individuals in the Saratov population had heterozygous inversions. Zygotic combinations of larvae in all the studied populations were different. PMID:25966581

  12. The spruce shoot gall midges (Diptera: Cecidomyiidae): Piceacecis, a new genus for a non-native pest of Norway spruce from Europe and its native American relative

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dasineura abietiperda (Henschel), a European pest of Norway spruce, Picea abies (Pinaceae), is reported as new to North America. Damage symptoms are illustrated and an outline of its biology is given. A new genus, Piceacecis Gagné is described to include it and its North American relative, Phytophag...

  13. Evaluation of corn plant as potential banker plant for supporting predatory gall Midge, Feltiella acarisuga (Diptera: Cecidomyiidae) against Tetranychus urticae (Acari: Tetranychidae) in greenhouse vegetable production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is one of the most important and highly polyphagous pests of vegetables and other crops worldwide. In this study, several experiments were conducted under laboratory and greenhouse conditions to evaluate whether corn plant ...

  14. Bioavailability, toxicity and biotransformation of selenium in midge (Chironomus dilutus) larvae exposed via water or diet to elemental selenium particles, selenite, or selenized algae.

    PubMed

    Gallego-Gallegos, Mercedes; Doig, Lorne E; Tse, Justin J; Pickering, Ingrid J; Liber, Karsten

    2013-01-01

    Elemental selenium (Se) is generally considered to be biologically inert due to its insolubility in water. It is a common form of Se in sediment near uranium mining and milling operations in northern Saskatchewan, Canada. Nanosized particles of many materials exhibit different properties compared with their bulk phases, in some cases posing health and ecological risks. Here we investigated the bioavailability and toxicity of Se nanoparticles (SeNPs) using 10-day waterborne and dietary exposures to larvae of Chironomus dilutus, a common benthic invertebrate. For comparison, larvae were also exposed to waterborne dissolved selenite and to dietary selenomethionine as selenized algae. Larval Se accumulation was evaluated using graphite furnace atomic absorption spectroscopy or inductively coupled plasma mass spectroscopy for total Se and X-ray absorption spectroscopy for Se chemical speciation. Exposure to nanoparticulate Se resulted in Se bioaccumulation, at high concentrations, inhibiting larval growth in both waterborne and dietary exposures; larvae predominantly accumulated selenomethionine-like species regardless of uptake route or form of Se tested. Despite the observed Se accumulation, our findings suggest there is little risk of direct SeNP toxicity to benthic invertebrates in Se-contaminated sediments in northern Saskatchewan. Nevertheless, elemental Se in sediments may be biologically available and may contribute directly or indirectly to the risk of Se toxicity to egg-laying vertebrates (fish and piscivorous birds) in Se-contaminated aquatic systems. It thus may be necessary to include elemental Se as a source of potential Se exposure in ecological risk assessments. PMID:23234498

  15. Serine and cysteine protease-like genes in the genome of a gall midge and their interactions with host plant genotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For plant-feeding insects, digestive proteases are targets for engineering protease inhibitors for pest control. In this study, we identified 105 putative serine- and cysteine-protease genes from Hessian fly genome. Among the genes, 31 encode putative trypsins, 18 encode putative chymotrypsins, se...

  16. Bluetongue virus surveillance in a newly infected area.

    PubMed

    Giovannini, A; Calistri, P; Conte, A; Savini, L; Nannini, D; Patta, C; Santucci, U; Caporale, V

    2004-01-01

    regions. For the risks related to animal movement, the surveillance data was used in risk assessment analyses to address the movement of slaughter and breeding animals from vaccinated/infected and surrounding areas to free areas. These risk assessments led to an amendment of the relevant European Union legislation. Finally, a Montecarlo simulation model was developed to simulate different sentinel system scenarios and to decrease the total number of sentinel animals and sites required by the surveillance system. The sentinel surveillance system was complemented by an entomological surveillance system based on the use of a number of permanent blacklight traps run weekly year-round and a number of mobile blacklight traps moved through the grid cells during the summer and autumn of each year. The aim of entomological surveillance was to define the maximum distribution of vectors and their seasonal population dynamics. Furthermore, the permanent trap system provides an early warning of the start of new epidemics. The data from the entomological surveillance system were also analysed to generate probability maps of the presence of the principal BTV vector (Culicoides imicola) and to define the geographical risk of BT on a nationwide basis, and to predict the geographical distribution and the short-term spread of C. imicola in Sardinia, using spatio-temporal data. The detection, since 2001, of BT outbreaks in the absence of C. imicola and the recent identification of BTV in midges of the Obsoletus Complex also stimulated investigations on other vector Culicoides, including C. obsoletus and C. pulicaris. PMID:20419661

  17. Bluetongue Virus NS4 Protein Is an Interferon Antagonist and a Determinant of Virus Virulence

    PubMed Central

    Ratinier, Maxime; Shaw, Andrew E.; Barry, Gerald; Gu, Quan; Di Gialleonardo, Luigina; Janowicz, Anna; Varela, Mariana; Randall, Richard E.; Caporale, Marco

    2016-01-01

    ABSTRACT Bluetongue virus (BTV) is the causative agent of bluetongue, a major infectious disease of ruminants with serious consequences to both animal health and the economy. The clinical outcome of BTV infection is highly variable and dependent on a variety of factors related to both the virus and the host. In this study, we show that the BTV nonstructural protein NS4 favors viral replication in sheep, the animal species most affected by bluetongue. In addition, NS4 confers a replication advantage on the virus in interferon (IFN)-competent primary sheep endothelial cells and immortalized cell lines. We determined that in cells infected with an NS4 deletion mutant (BTV8ΔNS4), there is increased synthesis of type I IFN compared to cells infected with wild-type BTV-8. In addition, using RNA sequencing (RNA-seq), we show that NS4 modulates the host IFN response and downregulates mRNA levels of type I IFN and interferon-stimulated genes. Moreover, using reporter assays and protein synthesis assays, we show that NS4 downregulates the activities of a variety of promoters, such as the cytomegalovirus immediate-early promoter, the IFN-β promoter, and a promoter containing interferon-stimulated response elements (ISRE). We also show that the NS4 inhibitory activity on gene expression is related to its nucleolar localization. Furthermore, NS4 does not affect mRNA splicing or cellular translation. The data obtained in this study strongly suggest that BTV NS4 is an IFN antagonist and a key determinant of viral virulence. IMPORTANCE Bluetongue is one of the main infectious diseases of ruminants and is caused by bluetongue virus (BTV), an arthropod-borne virus transmitted from infected to susceptible animals by Culicoides biting midges. Bluetongue has a variable clinical outcome that can be related to both virus and host factors. It is therefore critical to understand the interplay between BTV and the host immune responses. In this study, we show that a nonstructural protein

  18. Full-Genome Sequencing as a Basis for Molecular Epidemiology Studies of Bluetongue Virus in India

    PubMed Central

    Maan, Sushila; Maan, Narender S.; Belaganahalli, Manjunatha N.; Rao, Pavuluri Panduranga; Singh, Karam Pal; Hemadri, Divakar; Putty, Kalyani; Kumar, Aman; Batra, Kanisht; Krishnajyothi, Yadlapati; Chandel, Bharat S.; Reddy, G. Hanmanth; Nomikou, Kyriaki; Reddy, Yella Narasimha; Attoui, Houssam; Hegde, Nagendra R.; Mertens, Peter P. C.

    2015-01-01

    Since 1998 there have been significant changes in the global distribution of bluetongue virus (BTV). Ten previously exotic BTV serotypes have been detected in Europe, causing severe disease outbreaks in naïve ruminant populations. Previously exotic BTV serotypes were also identified in the USA, Israel, Australia and India. BTV is transmitted by biting midges (Culicoides spp.) and changes in the distribution of vector species, climate change, increased international travel and trade are thought to have contributed to these events. Thirteen BTV serotypes have been isolated in India since first reports of the disease in the country during 1964. Efficient methods for preparation of viral dsRNA and cDNA synthesis, have facilitated full-genome sequencing of BTV strains from the region. These studies introduce a new approach for BTV characterization, based on full-genome sequencing and phylogenetic analyses, facilitating the identification of BTV serotype, topotype and reassortant strains. Phylogenetic analyses show that most of the equivalent genome-segments of Indian BTV strains are closely related, clustering within a major eastern BTV ‘topotype’. However, genome-segment 5 (Seg-5) encoding NS1, from multiple post 1982 Indian isolates, originated from a western BTV topotype. All ten genome-segments of BTV-2 isolates (IND2003/01, IND2003/02 and IND2003/03) are closely related (>99% identity) to a South African BTV-2 vaccine-strain (western topotype). Similarly BTV-10 isolates (IND2003/06; IND2005/04) show >99% identity in all genome segments, to the prototype BTV-10 (CA-8) strain from the USA. These data suggest repeated introductions of western BTV field and/or vaccine-strains into India, potentially linked to animal or vector-insect movements, or unauthorised use of ‘live’ South African or American BTV-vaccines in the country. The data presented will help improve nucleic acid based diagnostics for Indian serotypes/topotypes, as part of control strategies. PMID

  19. Possible routes of introduction of bluetongue virus serotype 8 into the epicentre of the 2006 epidemic in north-western Europe.

    PubMed

    Mintiens, K; Méroc, E; Mellor, P S; Staubach, C; Gerbier, G; Elbers, A R W; Hendrickx, G; De Clercq, K

    2008-10-15

    In August 2006, bluetongue (BT) was notified in The Netherlands on several animal holdings. This was the onset of a rapidly spreading BT-epidemic in north-western Europe (latitude >51 degrees N) that affected cattle and sheep holdings in The Netherlands, Belgium, Germany, France and Luxembourg. The outbreaks were caused by bluetongue virus (BTV) serotype 8, which had not been identified in the European Union before. Bluetongue virus can be introduced into a free area by movement of infected ruminants, infected midges or by infected semen and embryos. In this study, information on animal movements or transfer of ruminant germ plasms (semen and embryos) into the Area of First Infection (AFI), which occurred before and during the onset of the epidemic, were investigated in order to establish the conditions for the introduction of this virus. All inbound transfers of domestic or wild ruminants, non-susceptible mammal species and ruminant germ plasms into the AFI during the high-risk period (HRP), registered by the Trade Control and Expert System (TRACES) of the EC, were obtained. Imports originating from countries with a known or suspected history of BTV-incidence of any serotype were identified. The list of countries with a reported history of BTV incidence was obtained from the OIE Handistatus II for the period from 1996 until 2004. No ruminants were imported from a Member State (MS) with a known history of BTV-8 or from any other country with a known or suspected history of BTV incidence of any serotype. Of all non-susceptible mammal species only 233 horses were transported directly into the AFI during the HRP. No importations of semen or embryos into the AFI were registered in TRACES during the period of interest. An obvious source for the introduction of BTV-8, such as import of infected ruminants, could not be identified and the exact origin and route of the introduction of BTV-8 thus far remains unknown. However, the absence of legal import of ruminants from

  20. Evolution of Bluetongue Virus Serotype 1 in Northern Australia over 30 Years

    PubMed Central

    Amos-Ritchie, Rachel; Broz, Ivano; Melville, Lorna; Flanagan, David; Davis, Steven; Hunt, Neville; Weir, Richard

    2014-01-01

    ABSTRACT Bluetongue virus serotype 1 (BTV 1) was first isolated in Australia from cattle blood collected in 1979 at Beatrice Hill Farm (BHF), Northern Territory (NT). From long-term surveillance programs (1977 to 2011), 2,487 isolations of 10 BTV serotypes were made. The most frequently isolated serotype was BTV 1 (41%, 1,019) followed by BTV 16 (17.5%, 436) and BTV 20 (14%, 348). In 3 years, no BTVs were isolated, and in 12 years, no BTV 1 was isolated. Seventeen BTV 1 isolates were sequenced and analyzed in comparison with 10 Australian prototype serotypes. BTV 1 showed an episodic pattern of evolutionary change characterized by four distinct periods. Each period consisted primarily of slow genetic drift which was punctuated from time to time by genetic shifts generated by segment reassortment and the introduction of new genome segments. Evidence was found for coevolution of BTV genome segments. Evolutionary dynamics and selection pressure estimates showed strong temporal and clock-like molecular evolutionary dynamics of six Australian BTV genome segments. Bayesian coalescent estimates of mean substitution rates clustered in the range of 3.5 × 10−4 to 5.3 × 10−4 substitutions per site per year. All BTV genome segments evolved under strong purifying (negative) selection, with only three sites identified as under pervasive diversifying (positive) selection. The obligate replication in alternate hosts (insect vector and vertebrate hosts) imposed strong evolutionary constraints. The dominant mechanism generating genetic diversity of BTV 1 at BHF was through the introduction of new viruses and reassortment of genome segments with existing viruses. IMPORTANCE Bluetongue virus (BTV) is the causative agent of bluetongue disease in ruminants. It is a disease of concern globally and is transmitted by biting midges (Culicoides species). Analysis of the evolutionary and selection pressures on BTV 1 at a single surveillance site in northern Australia showed strong

  1. Detection of bluetongue virus RNA in field-collected Culicoides spp. (Diptera: Ceratopogonidae) following the discovery of bluetongue virus serotype 1 in white-tailed deer and cattle in Louisiana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In November 2004, bluetongue virus (family Reoviridae, genus Orbivirus, BTV) serotype 1 (BTV-1) was detected for the first time in the United States from a hunter-killed deer in St. Mary Parish, LA. In 2005, sera surveys were conducted on three cattle farms near the area where the deer was found, an...

  2. TRANSMISSION OF ASCOVIRUS FROM HELIOTHIS VIRESCENS (LEPIDOPTERA: NOCTUIDAE) BY THREE PARASITOIDS AND EFFECTS OF VIRUS ON SURVIVAL OF PARASITOID CARDIOCHILES NIGRICEPS (HYMENOPTERA: BRACONIDAE).

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We demonstrated that a TBW ascovirus was vectored by the parasitoid Cardiochiles nigriceps (CN) Viereck to healthy TBW larval hosts in the field, and laboratory females of the braconids CN and Microplitis croceipes (MC) Cresson and the ichneumonid Campoletis sonorensis (CS) Cameron can transmit the ...

  3. ACUTE TOXICITY OF AQUEOUS AND CHIRNONOMUS DECORUS

    EPA Science Inventory

    Fourth instar larvae of the midge, Chironomus decorus, were exposed copper in water and copper in food and substrate (bound forms). opper present in aqueous forms was more toxic than when it was present in bound forms. he relationship between copper in water and copper in midges ...

  4. FATE OF BACILLUS SPHAERICUS 2362 SPORES FOLLOWING INGESTION BY NONTARGET INVERTEBRATES

    EPA Science Inventory

    Elimination of Bacillus sphaericus spores ingested by midge larvae, snails and oysters was most rapid among midge larvae. pores remained in oysters up to 21 days and in snails up to 49 days. Viable spores were recovered in snail and oyster feces for these same periods. here was n...

  5. Grain sorghum hybrid resistance to insect and bird damage - 2011

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nine grain sorghum hybrids were evaluated for resistance to sorghum midge and bird damage in 2011. Although their damage was relatively low in general in 2011, nine insect pests were observed on sorghum in south Georgia. They could be listed in order of importance as follows: sorghum midge, leaf-f...

  6. Systemic Imidacloprid Affects Intraguild Parasitoids Differently

    PubMed Central

    Roe, R. Michael; Bacheler, Jack S.

    2015-01-01

    Toxoneuron nigriceps (Viereck) (Hymenoptera, Braconidae) and Campoletis sonorensis (Cameron) (Hymenoptera, Ichneumonidae) are solitary endoparasitoids of the tobacco budworm, Heliothis virescens (Fabricius) (Lepidoptera, Noctuidae). They provide biological control of H. virescens populations in Southeastern US agricultural production systems. Field and greenhouse experiments conducted from 2011–2014 compared parasitism rates of parasitoids that developed inside H. virescens larvae fed on tobacco plants treated with and without imidacloprid. The parasitoids in our study did not have a similar response. Toxoneuron nigriceps had reduced parasitism rates, but parasitism rates of C. sonorensis were unaffected. Preliminary data indicate that adult female lifespans of T. nigriceps are also reduced. ELISA was used to measure concentrations of neonicotinoids, imidacloprid and imidacloprid metabolites in H. virescens larvae that fed on imidacloprid-treated plants and in the parasitoids that fed on these larvae. Concentrations were detectable in the whole bodies of parasitized H. virescens larvae, T. nigriceps larvae and T. nigriceps adults, but not in C. sonorensis larvae and adults. These findings suggest that there are effects of imidacloprid on multiple trophic levels, and that insecticide use may differentially affect natural enemies with similar feeding niches. PMID:26658677

  7. Systemic Imidacloprid Affects Intraguild Parasitoids Differently.

    PubMed

    Taylor, Sally V; Burrack, Hannah J; Roe, R Michael; Bacheler, Jack S; Sorenson, Clyde E

    2015-01-01

    Toxoneuron nigriceps (Viereck) (Hymenoptera, Braconidae) and Campoletis sonorensis (Cameron) (Hymenoptera, Ichneumonidae) are solitary endoparasitoids of the tobacco budworm, Heliothis virescens (Fabricius) (Lepidoptera, Noctuidae). They provide biological control of H. virescens populations in Southeastern US agricultural production systems. Field and greenhouse experiments conducted from 2011-2014 compared parasitism rates of parasitoids that developed inside H. virescens larvae fed on tobacco plants treated with and without imidacloprid. The parasitoids in our study did not have a similar response. Toxoneuron nigriceps had reduced parasitism rates, but parasitism rates of C. sonorensis were unaffected. Preliminary data indicate that adult female lifespans of T. nigriceps are also reduced. ELISA was used to measure concentrations of neonicotinoids, imidacloprid and imidacloprid metabolites in H. virescens larvae that fed on imidacloprid-treated plants and in the parasitoids that fed on these larvae. Concentrations were detectable in the whole bodies of parasitized H. virescens larvae, T. nigriceps larvae and T. nigriceps adults, but not in C. sonorensis larvae and adults. These findings suggest that there are effects of imidacloprid on multiple trophic levels, and that insecticide use may differentially affect natural enemies with similar feeding niches. PMID:26658677

  8. High Prevalence of Mansonella perstans Filariasis in Rural Senegal

    PubMed Central

    Bassene, Hubert; Sambou, Masse; Fenollar, Florence; Clarke, Siân; Djiba, Sawdiatou; Mourembou, Gaël; L. Y., Alioune Badara; Raoult, Didier; Mediannikov, Oleg

    2015-01-01

    Large parts of African and American countries are colonized by Mansonella, a very common but poorly described filarial nematode. Bloodsucking flies of the genus Culicoides are suspected to be the vector of Mansonella perstans, but no study in Senegal has confirmed that Culicoides can transmit the parasite. Designed specific real-time quantitative polymerase chain reaction (qPCR) can be used to identify microfilaria in stained blood smears. This study was performed in July and December 2010 in the southeastern Senegal, which is known to be endemic for M. perstans. We analyzed 297 blood smears from febrile and afebrile resident people by qPCR. The global prevalence of M. perstans was approximately 14.5% in both febrile and afebrile individuals. The age group of > 30 years had the highest prevalence (22.0%). No Culicoides among 1,159 studied specimens was positive for M. perstans and its vector in Senegal still requires identification. PMID:26078318

  9. IN SITU BIOASSAY CHAMBER FOR ASSESSMENT OF SEDIMENT TOXICITY AND BIOACCUMULATION USING BENTHIC INVERTEBRATES

    EPA Science Inventory

    In this study, we describe the construction of a simple, inexpensive bioassay chamber for testing sediment toxicity (survival and growth) and bioaccumulation under field conditions using the midge Chironomus tentans and the oligochaete Lumbriculus variegatus. The test chamber is ...

  10. Time-Frequency Analysis Reveals Pairwise Interactions in Insect Swarms

    NASA Astrophysics Data System (ADS)

    Puckett, James G.; Ni, Rui; Ouellette, Nicholas T.

    2015-06-01

    The macroscopic emergent behavior of social animal groups is a classic example of dynamical self-organization, and is thought to arise from the local interactions between individuals. Determining these interactions from empirical data sets of real animal groups, however, is challenging. Using multicamera imaging and tracking, we studied the motion of individual flying midges in laboratory mating swarms. By performing a time-frequency analysis of the midge trajectories, we show that the midge behavior can be segmented into two distinct modes: one that is independent and composed of low-frequency maneuvers, and one that consists of higher-frequency nearly harmonic oscillations conducted in synchrony with another midge. We characterize these pairwise interactions, and make a hypothesis as to their biological function.

  11. Oviposition behavior of the biological control agent Aphidoletes aphidimyza (Diptera: Cecidomyiidae) in environments with multiple pest aphid species (Hemiptera: Aphididae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Natural enemies are constantly faced with oviposition decisions that have potential fitness consequences. We investigated the oviposition behavior of the aphidophagous midge Aphidoletes aphidimyza (Diptera: Cecidomyiidae) when faced with multiple prey choices, i.e. plants infested with Myzus persic...

  12. Time-Frequency Analysis Reveals Pairwise Interactions in Insect Swarms.

    PubMed

    Puckett, James G; Ni, Rui; Ouellette, Nicholas T

    2015-06-26

    The macroscopic emergent behavior of social animal groups is a classic example of dynamical self-organization, and is thought to arise from the local interactions between individuals. Determining these interactions from empirical data sets of real animal groups, however, is challenging. Using multicamera imaging and tracking, we studied the motion of individual flying midges in laboratory mating swarms. By performing a time-frequency analysis of the midge trajectories, we show that the midge behavior can be segmented into two distinct modes: one that is independent and composed of low-frequency maneuvers, and one that consists of higher-frequency nearly harmonic oscillations conducted in synchrony with another midge. We characterize these pairwise interactions, and make a hypothesis as to their biological function. PMID:26197145

  13. Consequences of physical disturbance by tadpoles and snails on chironomid larvae.

    PubMed

    Pal, Gargi; Aditya, Gautam; Hazra, Niladri

    2014-01-01

    Indirect interactions among community members impact on organisms. The effects of two snails, banded pond snail, Bellamya bengalensis (Lamarck), and Red-rimmed melania, Melanoides tuberculata (Müller), and tadpoles of Asian common toad, Duttaphrynus melanostictus (Schneider), on nonbiting midge larvae, Chironomus striatipennis Kieffer, were observed in experimental microcosm. Decrease in tube number and tube length of midge larvae was observed compared to control condition due to introduction of selected above mentioned organisms. The direct effects of non-predator organisms on the midge larvae are due to physical disturbance that destroys their tubes. This may result in vulnerability of midge larvae to predators in the wild. So the community structure may be altered by indirect effects, where one or more species, through their direct disturbance, indirectly change the abundance of other species. PMID:24672384

  14. Consequences of Physical Disturbance by Tadpoles and Snails on Chironomid Larvae

    PubMed Central

    Pal, Gargi; Aditya, Gautam; Hazra, Niladri

    2014-01-01

    Indirect interactions among community members impact on organisms. The effects of two snails, banded pond snail, Bellamya bengalensis (Lamarck), and Red-rimmed melania, Melanoides tuberculata (Müller), and tadpoles of Asian common toad, Duttaphrynus melanostictus (Schneider), on nonbiting midge larvae, Chironomus striatipennis Kieffer, were observed in experimental microcosm. Decrease in tube number and tube length of midge larvae was observed compared to control condition due to introduction of selected above mentioned organisms. The direct effects of non-predator organisms on the midge larvae are due to physical disturbance that destroys their tubes. This may result in vulnerability of midge larvae to predators in the wild. So the community structure may be altered by indirect effects, where one or more species, through their direct disturbance, indirectly change the abundance of other species. PMID:24672384

  15. EFFECTS OF SYNTHETIC POLYELECTROLYTES ON SELECTED AQUATIC ORGANISMS

    EPA Science Inventory

    The acute toxicity of several polyelectrolytes to daphnids (Daphnia magna), fathead minnows (Pimephales promelas), gammarids (Gammarus pseudolimnaeus) and midges (Paratanytarsus parthenogeneticus) was tested. Most nonionic and anionic polyelectrolytes were not toxic at 100 mg/l w...

  16. Ancient carbon from a melting glacier gives high ¹⁴C age in living pioneer invertebrates.

    PubMed

    Hågvar, Sigmund; Ohlson, Mikael

    2013-01-01

    Glaciers are retreating and predatory invertebrates rapidly colonize deglaciated, barren ground. The paradox of establishing predators before plants and herbivores has been explained by wind-driven input of invertebrate prey. Here we present an alternative explanation and a novel glacier foreland food web by showing that pioneer predators eat locally produced midges containing 21,000 years old ancient carbon released by the melting glacier. Ancient carbon was assimilated by aquatic midge larvae, and terrestrial adults achieved a radiocarbon age of 1040 years. Terrestrial spiders, harvestmen and beetles feeding on adult midges had radiocarbon ages of 340-1100 years. Water beetles assumed to eat midge larvae reached radiocarbon ages of 1100-1200 years. Because both aquatic and terrestrial pioneer communities use ancient carbon, the term "primary succession" is questionable in glacier forelands. If our "old" invertebrates had been collected as subfossils and radiocarbon dated, their age would have been overestimated by up to 1100 years. PMID:24084623

  17. FATE OF BACILLUS SPHAERICUS 2362 SPORES IN NONTARGET INVERTEBRATES

    EPA Science Inventory

    Predatory stonefly larvae (Paragnetina media) acquired B. sphaericus spores by eating spore-laden midge larvae. eaf shredding stonefly larvae (Pteronarcys proteus) and cranefly larvae (Tipula abdominalis) acquired spores by feeding on contaminated leaf discs. pon switching to unc...

  18. Quantifying aquatic insect deposition from lake to land.

    PubMed

    Dreyer, Jamin; Townsend, Philip A; Hook, James C; Hoekman, David; Vander Zanden, M Jake; Gratton, Claudio

    2015-02-01

    Adjacent ecosystems are influenced by organisms that move across boundaries, such as insects with aquatic larval stages and terrestrial adult stages, which transport energy and nutrients from water to land. However, the ecosystem-level effect of aquatic insects on land has generally been ignored, perhaps because the organisms themselves are individually small. At the naturally productive Lake Mývatn, Iceland, we used two readily measured quantities: total insect emergence from water and relative insect density on land, to demonstrate an approach for estimating aquatic insect deposition (e.g., kg N x m(-2) x yr(-1)) to shore. Estimates from emergence traps between 2008 and 20.11 indicated a range of 0.15-3.7 g x m(-2) x yr(-1), or a whole-lake emergence of 3.1-76 Mg/yr; all masses are given as dry mass. Using aerial infall trap measurements of midge relative abundance over land, we developed a local-maximum decay function model to predict proportional midge deposition with distance from the lake. The dispersal model predicted midge abundance with R2 = 0.89, a pattern consistent among years, with peak midge deposition occurring 20-25 m inland and 70% of midges deposited within 100 m of shore. During a high-midge year (2008), we estimate midge deposition within the first 50 m of shoreline to be 100 kg xha(-1) x yr(-1), corresponding to inputs of 10 kg N x ha(-1) x yr(-1) and 1 kg P x ha(-1) x yr(-1), or about three to five times above background terrestrial N deposition rates. Consistent with elevated N input where midges are most dense, we observed that soil available nitrate in resin bags decreases with increasing distance from the lake. Our approach, generalizable to other systems, shows that aquatic insects can be a major source of nutrients to terrestrial ecosystems and have the capacity to significantly affect ecosystem processes. PMID:26240871

  19. Shock chloramination: potential treatment for Chironomidae (Diptera) larvae nuisance abatement in water supply systems.

    PubMed

    Broza, M; Halpern, M; Teltsch, B; Porat, R; Gasith, A

    1998-08-01

    In the early 1990s, infestations of midge larvae (Chironomidae, Chironomus sp.) were discovered in the potable water system of Tel Aviv, Israel. Control measures, such as draining and cleaning tanks, spraying water into the tank's air space, and electrocution traps of midge adults, were either inadequate or ineffective. In this system, monochloramine concentrations of up to 0.75 mg/liter are used routinely as a secondary disinfectant. This chemical was tested in the laboratory as a toxicant of midge larvae. The mortality of 4th instar midge larvae after short exposure to high chloramine concentrations (LC50 values of 32 mg/liter for 75 min) suggested the efficacy of instituting a Shock Chloramination treatment program. Tanks were partially drained until they contained only 20 cm of water and were then temporarily disconnected. Chloramine was added to this water to produce a concentration of approximately 70 mg/liter for 1-2 h. Subsequently, all dead chironomids were flushed out, and the tank was refilled to attain the operational volume of water. A 2nd identical treatment of water in the tank was suggested 7 d later to kill midges from reproductive adults and egg-masses that survived the 1st treatment. This treatment program was tested in commercial covered tanks and gave complete control of these pests for 6-10 wk. These results suggest that this treatment program may effectively prevent midge outbreaks in Israel's drinking water supply system during the height of the summer. PMID:9725031

  20. The Dutch strain of BTV-8 in white-tailed deer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bluetongue virus (BTV), family Reoviridae, genus Orbivirus, contains ten double stranded RNA segments encoding at least ten viral proteins. Bluetongue (BT) is an arthropod-borne disease; transmission to ruminants, including cattle, sheep, goats, and deer species by bites of species of Culicoides. In...

  1. Spatio-temporal patterns of Epizootic Hemorrhagic Disease (EHD) occurrence in the Continental USA (1980-2010)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Statement of the hypothesis or research question. Epizootic Hemorrhagic Disease (EHD) is a Culicoides insect-borne viral disease of wild and domestic ruminants commonly reported in the USA. While the severity of disease varies by geographic location, mortality rates can be as high as 90...

  2. Epizootic Haemorrhagic Disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Epizootic haemorrhagic disease (EHD) is an infectious non contagious viral disease transmitted by insects of the genus Culicoides which affects wild and domestic ruminants. The causative agent, the epizootic haemorrhagic disease virus (EHDV), belongs to the family Reoviridae, genus Orbivirus and sha...

  3. Comparison of cellular and humoral immunoassays for the assessment of summer eczema in horses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to compare and analyze three common diagnostic methods for summer eczema (SE) in horses, an allergic dermatitis caused by bites of Culicoides spp. Nine horses with a medical history of SE and nine control animals were intradermally challenged with whole body extracts ...

  4. Detection of a Novel Reassortant Epizootic Hemorrhagic Disease Virus in the United States Containing RNA Segments Derived from Both Exotic and Endemic Serotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Epizootic hemorrhagic disease virus (EHDV) is a Culicoides-transmitted orbivirus that infects domestic and wild ruminants and is provisionally distributed throughout Africa, North America, Australia, East Asia, and the Middle East. Historically, of the seven proposed serotypes of EHDV, only EHDV-1 a...

  5. [Risk assessment of bluetongue disease incursion into Germany using geographic information system (GIS)].

    PubMed

    Koslowsky, Sylvia; Staubach, Christoph; Kramer, Mathias; Wieler, Lothar H

    2004-01-01

    Using a geographic information system (GIS), by analysis of the relationship between the spatial distribution of cattle density and the risk factors temperature, altitude and rainfall, we defined geographical habitats enabling optimal development and competence of Culicoides spp. to transmit Bluetongue-Virus (BTV): Risk zones (low, high, highest risk) were identified mainly in Baden-Württemberg, Hessen and Rheinland-Pfalz if persistently infected ruminants are imported into these zones in summer (June to August mainly), based on the current climatic conditions, BTD outbreaks are considered a real possibility. Overwintering of the virus seems unlikely. However, global warming will lead to a steady increase of the size of the risk zones. In addition, the possibility of primary outbreaks increases. The reason for this is not only the expected northern shift of Culicoides imicola, but in addition an increasing vector competence of domestic Culicoides species. We therefore recommend the storage of vaccines as well as conducting ecological studies analysing the presence of Culicoides vectors. Using the data from these studies, it will be possible to produce updated quantitative risk assessment via GIS. PMID:15188681

  6. Antimicrobial Susceptibility of Bacillus Strains Isolated from Primary Starters for African Traditional Bread Production and Characterization of the Bacitracin Operon and Bacitracin Biosynthesis

    PubMed Central

    Sørensen, Kim I.; Thorsen, Line; Stuer-Lauridsen, Birgitte; Abdelgadir, Warda S.; Nielsen, Dennis S.; Derkx, Patrick M. F.; Jespersen, Lene

    2012-01-01

    Bacillus spp. are widely used as feed additives and probiotics. However, there is limited information on their resistance to various antibiotics, and there is a growing concern over the transfer of antibiotic resistance genes. The MIC for 8 antibiotics was determined for 85 Bacillus species strains, Bacillus subtilis subsp. subtilis (n = 29), Bacillus licheniformis (n = 38), and Bacillus sonorensis (n = 18), all of which were isolated from starters for Sudanese bread production. All the strains were sensitive to tetracycline (8.0 mg/liter), vancomycin (4.0 mg/liter), and gentamicin (4.0 mg/liter) but resistant to streptomycin. Sensitivity to clindamycin, chloramphenicol, and kanamycin was species specific. The erythromycin resistance genes ermD and ermK were detected by PCR in all of the erythromycin-resistant (MIC, ≥16.0 mg/liter) B. licheniformis strains and one erythromycin-sensitive (MIC, 4.0 mg/liter) B. licheniformis strain. Several amino acid changes were present in the translated ermD and ermK nucleotide sequences of the erythromycin-sensitive strain, which could indicate ErmD and ErmK protein functionalities different from those of the resistance strains. The ermD and ermK genes were localized on an 11.4-kbp plasmid. All of the B. sonorensis strains harbored the bacitracin synthetase gene, bacA, and the transporter gene bcrA, which correlated with their observed resistance to bacitracin. Bacitracin was produced by all the investigated species strains (28%), as determined by ultra-high-definition quadrupole time-of-flight liquid chromatography-mass spectrometry (UHD-QTOF LC/MS). The present study has revealed species-specific variations in the antimicrobial susceptibilities of Bacillus spp. and provides new information on MIC values, as well as the occurrence of resistance genes in Bacillus spp., including the newly described species B. sonorensis. PMID:22941078

  7. Food of freshwater drum in western Lake Erie

    USGS Publications Warehouse

    Bur, Michael T.

    1982-01-01

    The abundance of freshwater drum (Aplodinotus grunniens) suggests they play an important role in the Lake Erie ecosystem. Our analysis of freshwater drum digestive tracts and macrobenthic samples collected from western Lake Erie indicates that drum were selective feeders. Planktonic cladocerans and larval midges (Chironomidae) were the primary prey organisms eaten by drum. Young-of-the-year fed mostly on cladocerans, while yearling and older drum ate both cladocerans and midge larvae. Decapods, pelecypods, and fish were found only in the digestive tracts of drum longer than 250 mm. While the most abundant organisms in benthic samples were cladocerans (ephippial) and oligochaetes (89.5% by number), they constituted less than 1% of the diet. An evaluation of food selectivity, using Ivlev's index of electivity for benthic organisms, indicated that adult drum preferred midges to any other benthic food.

  8. Assessing the Economic Importance of Dasineura oxycoccana (Diptera: Cecidomyiidae) in Northern Highbush Blueberries.

    PubMed

    Hahn, Noel G; Isaacs, Rufus

    2015-08-01

    Infestation by blueberry gall midge, Dasineura oxycoccana Johnson, is common in northern highbush blueberries, but its effects on crop productivity are unknown. We examined whether infestation by blueberry gall midge reduces flower bud production when compared with uninfested shoots, and how infestation at different times affects the crop response. From the fall of 2009 to the spring of 2011, the number of flower buds on infested and uninfested shoots of blueberry bushes was counted and compared. Despite causing branching of vegetative growth, there was no significant effect of infestation on flower bud production. During the summer of 2010, damaged shoots were marked throughout the growing season in June, July, or August. The number of flower buds set per shoot declined with later infestation dates, and shoots damaged in August had significantly fewer buds than those damaged in June and July. We discuss the implications of these findings for management of blueberry gall midge in northern highbush blueberry. PMID:26470334

  9. Identifying consumer-resource population dynamics using paleoecological data.

    PubMed

    Einarsson, Árni; Hauptfleisch, Ulf; Leavitt, Peter R; Ives, Anthony R

    2016-02-01

    Ecologists have long been fascinated by cyclic population fluctuations, because they suggest strong interactions between exploiter and victim species. Nonetheless, even for populations showing high-amplitude fluctuations, it is often hard to identify which species are the key drivers of the dynamics, because data are generally only available for a single species. Here, we use a paleoecological approach to investigate fluctuations in the midge population in Lake Mývatn, Iceland, which ranges over several orders of magnitude in irregular, multigeneration cycles. Previous circumstantial evidence points to consumer-resource interactions between midges and their primary food, diatoms, as the cause of these high-amplitude fluctuations. Using a pair of sediment cores from the lake, we reconstructed 26 years of dynamics of midges using egg remains and of algal groups using diagnostic pigments. We analyzed these data using statistical methods that account for both the autocorrelated nature of paleoecological data and measurement error caused by the mixing of sediment layers. The analyses revealed a signature of consumer-resource interactions in the fluctuations of midges and diatoms: diatom abundance (as inferred from biomarker pigment diatoxanthin) increased when midge abundance was low, and midge abundance (inferred from egg capsules) decreased when diatom abundance was low. Similar patterns were not found for pigments characterizing the other dominant primary producer group in the lake (cyanobacteria), subdominant algae (cryptophytes), or ubiquitous but chemically unstable biomarkers of total algal abundance (chlorophyll a); however, a significant but weaker pattern was found for the chemically stable indicator of total algal populations (β-carotene) to which diatoms are the dominant contributor. These analyses provide the first paleoecological evaluation of specific trophic interactions underlying high amplitude population fluctuations in lakes. PMID:27145611

  10. A novel EPS-producing strain of Bacillus licheniformis isolated from a shallow vent off Panarea Island (Italy).

    PubMed

    Spanò, Antonio; Gugliandolo, Concetta; Lentini, Valeria; Maugeri, Teresa L; Anzelmo, Gianluca; Poli, Annarita; Nicolaus, Barbara

    2013-07-01

    A haloalkaliphilic, thermophilic Bacillus strain (T14), isolated from a shallow hydrothermal vent of Panarea Island (Italy), produced a new exopolysaccharide (EPS). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain T14 was highly related (99 % similarity) to Bacillus licheniformis DSM 13(T) and Bacillus sonorensis DSM 13779(T). Further DNA-DNA hybridization analysis revealed 79.40 % similarity with B. licheniformis DSM 13(T) and 39.12 % with B. sonorensis DSM 13779(T). Sucrose (5 %) was the most efficient carbon source for growth and EPS production. The highest EPS production (366 mg l(-1)) was yielded in fermenter culture at 300 rpm after 48 h of incubation. The purified fraction EPS1 contained fructose/fucose/glucose/galactosamine/mannose in a relative proportion of 1.0:0.75:0.28:tr:tr and possessed a molecular weight of 1,000 kDa displaying a trisaccharide unit constituted by sugars with a β-manno-pyranosidic configuration. Screening for biological activity showed anti-cytotoxic effect of EPS1 against Avarol in brine shrimp test, indicating a potential use in the development of novel drugs. PMID:23397221

  11. Screening for Bacillus subtilis group isolates that degrade cyanogens at pH 4.5-5.0.

    PubMed

    Abban, Stephen; Brimer, Leon; Abdelgadir, Warda S; Jakobsen, Mogens; Thorsen, Line

    2013-01-15

    Cyanogenic food crops abound in nature with important crops like cassava forming the staple food for over half a billion people. Detoxification by hydrolysis of cassava cyanogenic glycosides often involves acid fermentation, and in some of these processes Bacillus species are encountered. Forty Bacillus spp. (20 Bacillus subtilis, 11 Bacillus licheniformis, 7 Bacillus sonorensis, 2 Bacillus cereus) isolated from acid fermented primary starters to produce Gergoush, a Sudanese fermented snack, were screened for their ability to grow and to hydrolyze linamarin, the major cyanogen found in cassava at pH levels below 5.0; also the cyanogen amygdalin was assessed. The B. subtilis isolates grew in both HCl and lactic acid environments from pH 4.5-6.0 while being able to break down the cyanogenic glycosides. The B. licheniformis and B. sonorensis isolates grew and degraded cyanogens at pH 5.0 in a HCl environment, while two B. cereus isolates used in the study showed no breakdown reaction under all conditions tested. One B. subtilis isolate was observed to have substrate specificity between the breakdown of linamarin and amygdalin. We conclude that some Bacillus spp. isolates are important in the microbiological breakdown of cyanogens in cassava fermentations even at pH 4.5-5.0 though further investigations are required. PMID:23261810

  12. Bluetongue virus and epizootic haemorrhagic disease of deer virus serotypes in northern Colombian cattle.

    PubMed Central

    Homan, E. J.; Taylor, W. P.; de Ruiz, H. L.; Yuill, T. M.

    1985-01-01

    There is recent evidence of bluetongue (BT) and epizootic haemorrhagic disease (EHD) virus infection of cattle in the American tropics, including BT group reactive antibody in Colombian cattle. These observations prompted a study to determine serologically the specific BT and EHD virus types present, and time of infection and to collect Culicoides spp. as potential vectors. A prospective study of BT and EHD virus infection was done on two farms in the Colombian department of Antioquia. Sequential sampling of young cattle indicated acquisition of neutralizing antibody to BT virus serotypes 12, 14 and 17, and EHD virus serotypes 1 and 2. Insect captures showed a high association of Culicoides insignis with infected cattle. PMID:2991365

  13. Trajectory analysis and bluetongue virus serotype 2 in Florida 1982.

    PubMed

    Sellers, R F; Maarouf, A R

    1989-01-01

    Examination of Northern Hemisphere synoptic charts and computation of backward trajectories indicated that Culicoides infected with bluetongue virus serotype 2 could have been carried on the wind and brought the virus to Florida on the afternoon of August 19, 1982 after leaving northern Cuba the previous evening. Flight would have occurred at a height of 1-1.5 km at temperatures of 15-17 degrees C. The distance of 500 km from northern Cuba to Ona would have been covered in 20 h at an average speed of 25 km h-1. Computation of trajectories indicated that a second electropherotype, Ona B, was unlikely to have been introduced by infected Culicoides. PMID:2536578

  14. Equine insect bite hypersensitivity: what do we know?

    PubMed

    Schaffartzik, A; Hamza, E; Janda, J; Crameri, R; Marti, E; Rhyner, C

    2012-06-30

    Insect bite hypersensitivity (IBH) is an allergic dermatitis of the horse caused by bites of insects of the genus Culicoides and is currently the best characterized allergic disease of horses. This article reviews knowledge of the immunopathogenesis of IBH, with a particular focus on the causative allergens. Whereas so far hardly any research has been done on the role of antigen presenting cells in the pathogenesis of IBH, recent studies suggest that IBH is characterized by an imbalance between a T helper 2 (Th2) and regulatory T cell (T(reg)) immune response, as shown both locally in the skin and with stimulated peripheral blood mononuclear cells. Various studies have shown IBH to be associated with IgE-mediated reactions against salivary antigens from Culicoides spp. However, until recently, the causative allergens had not been characterized at the molecular level. A major advance has now been made, as 11 Culicoides salivary gland proteins have been identified as relevant allergens for IBH. Currently, there is no satisfactory treatment of IBH. Characterization of the main allergens for IBH and understanding what mechanisms induce a healthy or allergic immune response towards these allergens may help to develop new treatment strategies, such as immunotherapy. PMID:22575371

  15. A preventive immunization approach against insect bite hypersensitivity: Intralymphatic injection with recombinant allergens in Alum or Alum and monophosphoryl lipid A.

    PubMed

    Jonsdottir, Sigridur; Svansson, Vilhjalmur; Stefansdottir, Sara Bjork; Schüpbach, Gertraud; Rhyner, Claudio; Marti, Eliane; Torsteinsdottir, Sigurbjorg

    2016-04-01

    Insect bite hypersensitivity (IBH) is an IgE-mediated dermatitis of horses caused by bites of Culicoides insects, not indigenous to Iceland. Horses born in Iceland and exported to Culicoides-rich areas are frequently affected with IBH. The aims of the study were to compare immunization with recombinant allergens using the adjuvant aluminum hydroxide (Alum) alone or combined with monophosphoryl lipid A (MPLA) for development of a preventive immunization against IBH. Twelve healthy Icelandic horses were vaccinated intralymphatically three times with 10 μg each of four recombinant Culicoides nubeculosus allergens in Alum or in Alum/MPLA. Injection with allergens in both Alum and Alum/MPLA resulted in significant increase in specific IgG subclasses and IgA against all r-allergens with no significant differences between the adjuvant groups. The induced antibodies from both groups could block binding of allergen specific IgE from IBH affected horses to a similar extent. No IgE-mediated reactions were induced. Allergen-stimulated PBMC from Alum/MPLA horses but not from Alum only horses produced significantly more IFNγ and IL-10 than PBMC from non-vaccinated control horses. In conclusion, intralymphatic administration of small amounts of pure allergens in Alum/MPLA induces high IgG antibody levels and Th1/Treg immune response and is a promising approach for immunoprophylaxis and immunotherapy against IBH. PMID:27032498

  16. Nest ectoparasites increase physiological stress in breeding birds: an experiment

    NASA Astrophysics Data System (ADS)

    Martínez-de La Puente, Josué; Merino, Santiago; Tomás, Gustavo; Moreno, Juan; Morales, Judith; Lobato, Elisa; Martínez, Javier

    2011-02-01

    Parasites are undoubtedly a biotic factor that produces stress. Heat shock proteins (HSPs) are important molecules buffering cellular damage under adverse conditions. During the breeding season, blue tit Cyanistes caeruleus (L.) adults are affected by blood parasites, nest-dwelling parasites and biting flies, potentially affecting their HSP-mediated responses. Here, we treated females with primaquine to reduce blood parasites and fumigated nests with permethrin to reduce nest-dwelling parasites to test whether these treatments affect HSP60 level during the breeding season. Medicated females, but not controls, had a significant reduction of the intensity of infection by Haemoproteus spp. blood parasites. However, final intensity of infection did not differ significantly between groups, and we did not find an effect of medication on change in HSP60 level. Fumigation reduced the abundance of nest-dwelling parasites (mites, fleas and blowfly larvae) and engorged biting midges in nests. Females breeding in non-fumigated nests increased HSP60 levels during the season more than those breeding in fumigated nests. Furthermore, the change in HSP60 level was positively correlated with the abundance of biting midges. These results show how infections by nest ectoparasites during the breeding period can increase the level of HSPs and suggest that biting midges impose physiological costs on breeding female blue tits. Although plausible, the alternative that biting midges prefer to feed on more stressed birds is poorly supported by previous studies.

  17. Effects of spatial and temporal variation of acid-volatile sulfide on the bioavailability of copper and zinc in freshwater sediments

    SciTech Connect

    Besser, J.M.; Ingersoll, C.G.; Giesy, J.P.

    1996-03-01

    Variation in concentrations of acid-volatile sulfide (AVS) in sediments from the upper Clark Fork River of Montana, USA, was associated with differences in bioaccumulation of Cu and Zn and growth of larvae of the midge, Chironomus tentans. Growth of midge larvae was significantly greater and bioaccumulation of Cu was significantly less in surface sections (0--3 cm depth) of sediment cores, which had greater concentrations of AVS and lesser ratios of simultaneously extracted metals to AVS (SEM:AVS ratios) than in subsurface sediments (6--9 cm). Concentrations of AVS were significantly less in sediments incubated with oxic overlying water for 9 weeks than in the same sediments incubated under anoxic conditions. Bioaccumulation of Cu differed significantly between incubation treatments, corresponding to differences in concentrations of AVS and SEM:AVS ratios, although midge growth did not. Bioaccumulation of Zn did not differ significantly between depth strata of sediment cores or between incubation treatments. When results from the two sets of bioassays were combined, bioaccumulation of Cu and Zn, but not growth, was significantly correlated with SEM:AVS ratios and other estimates of bioavailable metal fractions in sediments. Growth of midge larvae was significantly correlated with bioaccumulation of Zn, but not Cu, suggesting that Zn was the greater contributor to the toxicity of these sediments. Assessments of the toxicity of metal-contaminated freshwater sediments should consider the effects of spatial and temporal variation in AVS concentrations on metal bioavailability.

  18. First description of the male and additional data on the female morphology of Aprostocetus rubi Graham (Hymenoptera: Chalcidoidea: Eulophidae).

    PubMed

    Jałoszyński, Paweł

    2016-01-01

    The previously unknown male of Aprostocetus rubi Graham (Eulophidae: Tetrastichinae) was reared, together with females, from galls of the raspberry gall midge Lasioptera rubi (Schrank) (Diptera: Cecidomyiidae) collected in Central Poland. The male is described and illustrated for the first time, and additional information provided on the morphology of the female. PMID:27395694

  19. An Introduction to the Identification of Chironomid Larvae.

    ERIC Educational Resources Information Center

    Mason, William T., Jr.

    This publication is an introductory guide to the identification of Chironomid (Midge) larvae. The larvae of these small flies are an important link in the food chain between algae and microinvertebrates. As a family, the larvae exhibit a wide range of tolerance to environmental factors such as amounts and types of pollutants. Much of this…

  20. Review of Sunflower Insect Pest Problems in North Dakota in 2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The major insect pest species that cause economic losses to sunflower producers in North Dakota are red sunflower seed weevil, banded sunflower moth, and sunflower midge. New emerging insect pests include a longhorned beetle (Dectes texanus), sunflower seed maggot, sunflower bud moth, and lygus bug....

  1. Germplasm evaluation for resistance to insect pests of the sunflower head

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The key insect pests attacking the sunflower head and seeds include the sunflower moth, the red sunflower seed weevil, the banded sunflower moth, and the sunflower midge. There is a need to reduce losses from these pests by providing long-term economical management for sunflower growers. In 2005, su...

  2. Evaluation of sunflower for resistance to stem and seed pests in the northern and central Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The major insect pests attacking cultivated sunflower include the sunflower stem weevil, the sunflower moth, the red sunflower seed weevil, the banded sunflower moth, and the sunflower midge. Strategies to reduce crop losses for these pests have focused on insecticidal control, but host-plant resist...

  3. 78 FR 56744 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-13

    ... small probe (Minimally Invasive Direct Glacier Exploration MIDGE) equipped with a camera to visualize... approximately 50 meters and would not be near the glacier base or subglacial source of brine. Results from these... drilling would not go as deep as the base of the glacier or the source of the brine. Location: ASPA...

  4. A water-quality assessment of the Feather Creek watershed, Vermillion County, Indiana

    USGS Publications Warehouse

    Eikenberry, Stephen E.

    1977-01-01

    Navicula sp and Scenedesmus sp dominated the phydoplankton community at the site sampled and indicated an environment lacking in organic enrichment. Cladaphora sp dominated the periphyton community sampled. Benthic invertebrates sampled were mostly caddis flies (Cheumatopsyche sp) and midges (Orthocladius sp) and had a diversity index of 2.3, which indicates some organic enrichment of the stream.

  5. Ancient carbon from a melting glacier gives high 14C age in living pioneer invertebrates

    PubMed Central

    Hågvar, Sigmund; Ohlson, Mikael

    2013-01-01

    Glaciers are retreating and predatory invertebrates rapidly colonize deglaciated, barren ground. The paradox of establishing predators before plants and herbivores has been explained by wind-driven input of invertebrate prey. Here we present an alternative explanation and a novel glacier foreland food web by showing that pioneer predators eat locally produced midges containing 21,000 years old ancient carbon released by the melting glacier. Ancient carbon was assimilated by aquatic midge larvae, and terrestrial adults achieved a radiocarbon age of 1040 years. Terrestrial spiders, harvestmen and beetles feeding on adult midges had radiocarbon ages of 340–1100 years. Water beetles assumed to eat midge larvae reached radiocarbon ages of 1100–1200 years. Because both aquatic and terrestrial pioneer communities use ancient carbon, the term “primary succession” is questionable in glacier forelands. If our “old” invertebrates had been collected as subfossils and radiocarbon dated, their age would have been overestimated by up to 1100 years. PMID:24084623

  6. What Food and Feeding Rates are Optimum for the Chironomus dilutus Sediment Toxicity Test Method?

    EPA Science Inventory

    Laboratory tests with benthic macroinvertebrates are commonly used to assess the toxicity of both contaminated sediments and individual chemicals. Among the standard procedures for benthic macroinvertebrates are 10-d, 20-d, and life cycle exposures using the midge, Chironomus ...

  7. Recovery of macroinvertebrates by screening in the field: a comparison between coarse (1.18 mm) and fine (0.60 mm) mesh sieves

    USGS Publications Warehouse

    Dukerschein, J.T.; Gent, R.; Sauer, J.

    1996-01-01

    We evaluated the potential loss of target benthic macroinvertebrates from coarse-mesh field wash down of samples through a 1.18-mm mesh sieve nested on a 0.60-mm mesh sieve. Visible target organisms (midges, mayflies, and fingernail clams) in the 1.18-mm mesh sieve were removed from the sample and enumerated in the field. The entire contents of both sieves were preserved for subsequent laboratory enumeration under 4X magnification. Percent recoveries from each treatment were based on total intact organisms found in all sieves. Percent recovery for fingernail clams found in the field (31%) was lower than for mayflies (79%) and midges (88%). Laboratory enumeration of organisms retained by the 1.18-mm sieve yielded additional fingernail clams (to total 74% recovered in the field and lab), mayflies (to total 89%), and midges (to total 91%). If the 1.18-mm sieve is used alone in the field, it is adequate to monitor mayflies, midges >1 cm, and adult fingernail clams greater than or equal to 5.0 mm shell length.

  8. FAMILY CECIDOMYIIDAE.

    PubMed

    Maia, Valéria Cid

    2016-01-01

    This large family is poorly known in Colombia, where only 44 species have been recorded in 20 genera. All of them are included in Cecidomyiinae, which is the most diverse subfamily of gall midges in number of species and feeding habits, including phytophagous, predaceous and fungivorous species. Most of them are galler. The other subfamilies have never been recorded in this country. PMID:27395254

  9. INTERLABORATORY STUDY OF PRECISION: HYALELLA AZTECA AND CHIRONOMUS TENTANS FRESHWATER SEDIMENT TOXICITY ASSAYS

    EPA Science Inventory

    Standard 10-d whole sediment toxicity test methods have recently been developed by the U.S. Environmental Protection Agency (EPA) for the amphipod Hyalella azteca and the midge Chironomus tentans. An interlaboratory evaluation of method precision was performed using a group of se...

  10. Reduction of mosquito biting-pressure: spatial repellents or mosquito traps? A field comparison of seven commercially available products in Israel

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The personal protection capability of seven commercially available mosquito control devices (MCD) is compared under field conditions in Israel. Trials were performed in a high biting-pressure area inhabited by large populations of mosquito and biting midge species and using human volunteers for lan...

  11. Feltiella acarisuga (Vallot) (Insecta: Diptera: Cecidomyiidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The predatory gall midge, Feltiella acarisuga is one of the most effective and widespread natural enemies of spider mites. Because of their flying and prey detecting capabilities, and high feeding potential, it is considered an important natural enemy of the two-spotted spider mite in a number of cr...

  12. The Lowly Lakefly.

    ERIC Educational Resources Information Center

    Hein, John; Mahadeva, Madhu N.

    1988-01-01

    Describes the life cycle and requirements of midges. Discusses larval substrate preferences, swimming behavior and distribution, developmental rates, temperature tolerances, egg hatching, swarming flights of adults, species composition within a sampling site, and developing a reference collection by rearing larvae. (CW)

  13. North Dakota Sunflower Insect Pest Survey, 2006-2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The major insect pest species that cause economic losses to sunflower producers in North Dakota are banded sunflower moth (Cochylis hospes Walsingham), red sunflower seed weevil (Smicronyx fulvus Le Conte), and sunflower midge (Contarinia schulzi Gagne). New emerging insect pests include lygus bugs ...

  14. Establishment, population increase, spread, and ecological host range of Lophodiplosis trifida (Diptera: Cecidomyiidae), a biological control agent of the invasive tree Melaleuca quinquenervia (Myrtales:Myrtaceae).

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Australian tree Melaleuca quinquenervia (Cav.) Blake is an invasive weed in wetland systems of Florida, USA. A biological control program targeting M. quinquenervia has culminated in the release of the gall forming midge Lophodiplosis trifida Gagné (Cecidomyiidae). Populations of the introduced ...

  15. Human mesenchymal stromal cells could deliver erythropoietin and migrate to the basal layer of hair shaft when subcutaneously implanted in a murine model.

    PubMed

    Mok, P L; Cheong, S K; Leong, C F; Chua, K H; Ainoon, O

    2012-08-01

    Mesenchymal stromal cells (MSC) are an attractive cell-targeting vehicle for gene delivery. MIDGE (an acronym for Minimalistic, Immunologically Defined Gene Expression) construct is relatively safer than the viral or plasmid expression system as the detrimental eukaryotic and prokaryotic gene and sequences have been eliminated. The objective of this study was to test the ability of the human MSC (hMSC) to deliver the erythropoietin (EPO) gene in a nude mice model following nucleofection using a MIDGE construct. hMSC nucleofected with MIDGE encoding the EPO gene was injected subcutaneously in Matrigel at the dorsal flank of nude mice. Subcutaneous implantation of nucleofected hMSC resulted in increased hemoglobin level with presence of human EPO in the peripheral blood of the injected nude mice in the first two weeks post-implantation compared with the control groups. The basal layer of the hair shaft in the dermal layer was found to be significantly positive for immunohistochemical staining of a human EPO antibody. However, only a few basal layers of the hair shaft were found to be positively stained for CD105. In conclusion, hMSC harboring MIDGE-EPO could deliver and transiently express the EPO gene in the nude mice model. These cells could be localized to the hair follicle and secreted EPO protein might have possible role in hair regeneration. PMID:22560724

  16. Hessian fly - associated bacteria: transmission, essentiality, and composition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant-feeding insects have been recently found to use microbes to manipulate host plants. Gall midges are one of the largest groups of insects that manipulate host plants extensively. In this study, we systematically analyzed for the first time bacteria associated with the Hessian fly (HF, Mayetio...

  17. 78 FR 5351 - Endangered and Threatened Wildlife and Plants; Proposed Designation of Critical Habitat for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-25

    ... Federal Register on July 1, 1994 (59 FR 34271)), the Information Quality Act (section 515 of the Treasury... source of algae production and an aquatic insect food base consisting of caddisflies, mayflies, midges... continue to persist., Introduced species are a serious threat to native aquatic species (Miller 1961,...

  18. SURVIVAL AND ADULT EMERGENCE OF AQUATIC INSECTS IN AIR-SUPERSATURATED WATER

    EPA Science Inventory

    Mayflies Timpanoga hecuba, caddisflies Dicosmoecus gilvipes, mosquitoes Culex peus and midges Cricotopus sp. were tested in the laboratory to determine the effects of air-supersaturated water on survival and adult emergence. The acute 96-hour LC50 value (lethal concentration whic...

  19. Larvae of North American Eukiefferiella and Tvetenia (Diptera: Chironomidae). Bulletin No. 452.

    ERIC Educational Resources Information Center

    Bode, Robert W.

    "Eukiefferiella" and "Tvetenia" are closely related genera belonging to the subfamily Orthocladiinae within the Chironomidae, a family of non-biting midges. All known larvae in these genera are aquatic, being found predominantly in running water. Most species prefer cold, swift-flowing, well-oxygenated streams. Although larvae and pupae of these…

  20. Cloning and expression of an atrazine inducible cytochrome P450 from Chironomus tentans (Diptera: Chironomidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous studies performed in our lab have measured the effect of atrazine exposure on cytochrome P450-dependent monooxygenase activity and have found increased activity in midge larvae (Chironomus tentans) as a result of atrazine exposure (1-10 ppm). Here we report the cloning and expression of a ...