7 research outputs found

    Vespa Velutina - Les virus du frelon, une menace ou un espoir ?

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    National audienceDepuis son introduction en France en 2004, la frelon asiatique (Vespa velutina) s'est répandu en Europe, créant des difficultés considérables pour les apiculteurs dans certaines zones géographiques. Son impact va bien au-delà des abeilles prélevées devant les ruches : lorsque la pression des frelons augmente, pendant l'été, les abeilles diminuent considérablement leurs activités de butinage. Selon les situations, cette diminution de butinage peut entraîner une désertion de la colonie à l'automne, ou son effondrement pendant l'hiver. L'effet de l'introduction du frelon asiatique sur les autres communautés d'insectes est encore mal connu. A ce jour aucune mesure n'a permis d'éradiquer sa présence dès lors qu'il apparaît dans une nouvelle aire géographique. Dans ce contexte, nous nous sommes intéressés au cortège de virus présent chez le frelon asiatique, afin d'une part d'évaluer le risque de dissémination de ces agents pathogènes vers les espèces avec lesquelles le frelon interagit, et d'autre part de rechercher des virus qui pourraient être utilisés en lutte biologique

    Correlation between magnetic resonance, X-ray imaging alterations and histological changes in an ovine model of age-related disc degeneration

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    International audienceSheep are one of the many animal models used to investigate the pathophysiology of disc degeneration and the regenerative strategies for intervertebral disc (IVD) disease. To date, few studies have thoroughly explored ageing of ovine lumbar IVDs. Hence, the objective of the present study was to concomitantly assess the development of spontaneous age-related lumbar IVD degeneration in sheep using X-ray, magnetic resonance imaging (MRI) as well as histological analyses. 8 young ewes ( 48 months old) were included. Disc height, Pfirrmann and modified Pfirrmann grades as well as T2-wsi and T2 times were assessed by X-ray and MRI. The modified Boos score was also determined using histology sections. Pfirrmann (2 to 3) and modified Pfirrmann (2 to 4) grades as well as Boos scores (7 to 13) gradually increased with ageing, while T2-weighted signal intensity (1.18 to 0.75), T2 relaxation time (114.36 to 70.65 ms) and disc height (4.1 to 3.2 mm) decreased significantly. All the imaging modalities strongly correlated with the histology (p < 0.0001). The present study described the suitability of sheep as a model of age-related IVD degeneration by correlation of histological tissue alterations with the changes observed using X-ray and MRI. Given the structural similarities with humans, the study demonstrated that sheep warrant being considered as a pertinent animal model to investigate IVD regenerative strategies without induction of degeneration

    DURAPI – Vers une meilleure connaissance et un accompagnement technique des exploitations apicoles professionnelles : durabilité, stratégies de renouvellement du cheptel et conséquences sur le fonctionnement global de l’exploitation

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    Variability of the production context, colony losses: professional beekeepers have to cope with several environmental and socio-economic issues to ensure the sustainability of their farm. Thus, the DURAPI project aimed at developing a sustainability assessment framework for bee farming operations through a participatory design involving the stakeholders from the beekeeping sector. We also considered the part of the colony and queen replacement strategy, which is central in the colony management: the existing replacement strategies were identified and their possible consequences on the farm sustainability, in particular on the work organisation, were studied. These results allowed us to develop training tools for future beekeepers. This project also provides several support tools for beekeeping advisors.Variabilité du contexte de production, pertes de colonies d’abeilles : les exploitations apicoles font aujourd'hui face à différentes problématiques environnementales comme socio-économiques. Dans ce contexte, le projet DURAPI a visé à élaborer un cadre d’évaluation de la durabilité de ces exploitations, à travers une démarche participative qui a impliqué de nombreux acteurs de la filière. Parallèlement, la place de la gestion du renouvellement des colonies et des reines dans cette durabilité a été considérée. Les principales stratégies de renouvellement du cheptel mises en place dans les exploitations ont ainsi été identifiées afin d’ensuite caractériser leurs conséquences possibles sur cette durabilité de l’exploitation, notamment en termes de temps et d’organisation du travail. Ces différents résultats ont donné lieu à la création de supports pour les formateurs en apiculture. Les méthodes développées dans le cadre du projet peuvent par ailleurs être mobilisées pour l’appui aux apiculteurs ou futurs installés

    Mating disruption by vibrational signals: state of the field and perspectives

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    Until a few years ago, the concept of mating disruption had been exclusively associated with the use of pheromones to reduce population density of insect pests. Since the early 2000s, a novel approach has been proposed to the scientific community: vibrational mating disruption (VMD). The novelty is the use of disturbance vibrations to disrupt the mating behavior of insect pests that communicate by means of substrate-borne vibrations. This research falls within the new field of biotremology and it brought the VMD from a theoretical concept to practical open field experimentation: in 2017, VMD was applied in an organic vineyard in Northern Italy to control leafhopper pests’ population density. This achievement gave us the opportunity to report the state of the field for the method, to discuss the ongoing research and to make a comparison between pheromone mating disruption (PMD) and VMD. In this chapter, we review the salient moments that led to the field application of VMD. Then, we discuss the VMD characteristics and we provide a benchmark, using as reference the traditional PMD to discuss similarities and differences. Furthermore, we analyze the advantages and disadvantages of applying VMD to commercial crops. We are convinced that the first vibrational vineyard is a starting point and that biotremology will provide many innovative possibilities for farmers to control pests in the future. We also think that the introduction of electronic devices in the vineyard could be a trailblazer for the diffusion of smart technology in viticulture, thus improving its general management

    Biology and ecology of the Flavescence dorée vector Scaphoideus titanus: a review

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