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International audience; The lability of trace metals (TM) in the soil is time-dependent, and temporal changes in metals' state are known as "soil aging." However, there is no study assessing a long-term change in the environmental availability of metals and the effects of soil aging on the dynamics of bioaccumulation of TM in terrestrial wild mammals. This study aims to estimate whether and how soil aging affects the transfers of TM in terrestrial food webs. Based on long-term monitoring from 2006 to 2019 in metal-contaminated sites, we compared the temporal change in the availability of TM in the soil to temporal trends of TMs in small mammals' tissues.

Additional file 6: Figure S2. Box-plot illustrations showing for 1) upper panel, left mean cases of meningitis, right total cases of meningitis, and 2) lower panel, left max attack rate, and right mean attack rate, the variations during years. The red curves show the locally weighted non parametric regressions using a LOESS function (tension, t = 0.5), DRC, 2000–2012.

Additional file 7: Figure S3. Time-series decomposition using LOESS regression for meningitis, for primary cluster, secondary cluster 4 and secondary cluster 5, DRC, 2000–2012.

National audience; Echinococcus multilocularis (Em) est un cestode Responsable de l’échinococcose alvéolaire.Les carnivores hôtes définitifs abritent les vers adultes qui produisent des œufs (formes infectantes des rongeurs et de l’homme) répandus dans l’environnement avec les fèces. L’utilisation de marqueurs moléculaires permet d’identifier et de suivre des variants génétiques parasitaires dans la population vulpine. Cependant l’ADN est souvent extrait des vers adultes impliquant un piégeage et une autopsie pratiqués sur les carnivores. Nous avons développé une approche non invasive qui a consisté à typer un à un les œufs contenus dans des fèces de renard, chien et chat testées positives par une qPCR spécifique d’Em et à étudier leur variabilité génétique à l'aide du microsatellite EmsB. Des œufs d’Em ont été isolés par flottaison dans 1/3 (31/96) des fèces de carnivores (70 de renard, 15 de chien, 6 de chat) collectées dans un village situé en zone d’endémie de l’échinococcose alvéolaire (département du Doubs) et testées positives par la qPCR. En analyses préliminaires, 18 œufs isolés `a partir de 6 fèces de renard (1 à 4 œufs par fèces) présentaient 3 profils EmsB différents notifiés précédemment dans la région d’étude, en France et en Europe. Ces données confirment que la présence d’ADN du parasite ne présume pas de la présence des œufs. Une confirmation par flottaison est alors nécessairepour estimer le risque infectieux. Dans cette approche non invasive, l’isolement individuel des œufs a permis de mettre en évidence pour la première fois des profils EmsB à partir des fèces.

Poster; International audience; Ensuring traceability of field experimental data or laboratory sampling data to conduct reproducible research is a challenge at the present time. Between the time when geolocalized specimens (biotic or abiotic) are taken, and the time the resulting data ends up in analysis published within a study, many manual operations take place and may generate errors. The French LTSER have joined forces at the national level to propose a solution as generic as possible to this problem of monitoring of the samples and the data associated with them. Compared to existing solutions (such as Laboratory Information Management Systems), we target a robust labeling solution adapted to outdoor working conditions, with the management of stocks and movements of samples. We designed and realized a prototype tested from end to end, using an open source software (https://github.com/Irstea/collec), cheap Zebra printers (mobile or not) and raspberries as devices. This solution provides sufficient flexibility for the wide variety of existing protocols. Its strength is the record of all contextual data associated with the samples, which constitute important parameters of the subsequent analyzes. At last, not only traceability is guaranteed, but also a gain of time and a rationalization of the storage of samples that will induce a return on investment.

International audience

International audience; Trophic interactions, eg predation and herbivory, are one of the main biotic interactions driving the composition and functioning of terrestrial and aquatic food webs as they sustain energy and matter flows among organisms. The relationship between a resource availability and its consumption rate by a predator or herbivore, the functional response, is complex since often non-linear in shape and likely to depend upon the availability of other resources. Trophic interactions also nest the transmission of a large variety of multi-hosts parasites (ie trophically-transmitted parasites, TTP) within food webs. Moreover, the capacity to acquire, develop and transmit a parasite, called competence, vary among host species. The use of mathematical approaches, such as mechanistic dynamic models, to explore the transmission dynamics of TTP have often ignore the complexity of functional response and the variation in host competence. However, a prerequisite for understanding and modeling the ecology of TTP is to identify hosts species that are involved in transmission, ie the consumption of which ensures the parasite to step from the larval to the adult stage. This translates into the simple question “who is eating whom?”. Traditional techniques for investigating feces or stomach content based on macro- or microscopic identification of food remains fail to achieve fine taxonomic resolution identification of ingested items. Recently, DNA-based techniques such as metabarcoding have arisen as a powerful approach for the simultaneous taxonomic identification of several food items in feces or stomach content with high taxonomic resolution.We built a “one predator-two prey” eco-epidemiological model using a system of ordinary differential equations which allows for complex predation patterns. Using parameters related to Echinococcus multilocularis transmission in wildlife in Eastern France, we analyzed to what extent variations in prey diversity, total density and competence to transmit the parasite impact the basic reproductive number R0, which is a measure of disease outbreak risk. In parallel, we developed a molecular metabarcoding approach to investigate the diet of dog and red fox in rural settings of Eastern France, Gansu and Kyrgyzstan where E. multilocularis is endemic. Preliminary results, advantages and limitations, as well as perspectives of these recent developments will be presented.

High spin states in 80Sr have been studied using the techniques of in-beam γ-ray spectroscopy. The reaction used was 54Fe(29Si, 2pn)80Sr at beam energies between 85 and 110 MeV. γ-γ coincidence measurements were performed with a thin target to investigate the level structure. Both neutron gated and singles angular distribution measurements were carried out to aid in the assignment of level spins. The directional correlation ratios extracted from the γ-γ coincidence data provided a consistency check for the spin assignments. Level lifetimes were measured by the Doppler shift attenuation method in a thick target γ-γ coincidence measurement. The ground state band has been identified up to (26+) and three previously unobserved sidebands have been discovered. The deduced level scheme is compared with cranking model calculations; the predicted transformation to mostly non-collective excitations of an oblate shape is not observed experimentally. The behaviour of the J(1) and J(2) moments of inertia is discussed and presented as evidence for either static or dynamic γ-deformation in the light Sr isotopes. In addition, the level structure is compared with IBM-2 calculations. These calculations indicate the importance of proton excitations across the Z=40 subshell gap, into the g9/2 orbital, and suggest that the lowest lying 80Sr sideband can be identified with the collective IBM-2 quasi-γ band. NUCLEAR REACTIONS 54Fe(29Si, 2pn), ,em>E = 85 - 110 MeV; measured Eγ, Iγ(θ), γ-γ, n-γ coincidences, DCO ratios, Doppler shifted γ-ray lineshapes. 80Sr deduced levels, J, π, τ. Enriched target, Ge(Li), Ge, NE213 detectors.

Rapid expansion of oil palm cultivation in Southeast Asia raises concerns about biodiversity conservation. Moreover, rats are invasive pests in oil palm plantations, often causing substantial damages. In Indonesia, rat control is generally based on field treatment using anticoagulant rodenticides and/or on reinforcement of predation by barn owls (Tytoalba), by providing nest boxes within the plantation. Rodenticide use is costly for the producer and can indirectlypoison non-target species such as rat predators. Thus, biological control of rat pests should be promoted, both from conservation and production points of view. Within the assemblage of rat predators, small carnivores may contribute to rat population regulation. However the persistence of small carnivores within oil palm plantations, their habitat use, their diet and their contribution to rat control have been poorly investigated. We conducted a 3-year comparative study (2010-2012) in well-established oil palm plantations in Riau and Bangka provinces, in Indonesia: in both areas barn owl populationsare successfully reinforced, but in Riau rat populations have been maintained at an acceptable level without the use of rodenticide for more than 10 years, whereas in Bangka intensive rodenticide applications did not prevent high levels of rat damages. We compared those two contrasted systems in term of predator communities (barn owls and small carnivores) abundance and/or diet. In the poster, we will only present results related to small carnivores. Using a kilometric abundance index yielded from spotlight and faeces counts, we found that small carnivores were much more abundant in Riau plantations than in Bangka, and that the leopard cat (Prionailurus bengalensis) was the dominant species in Riau and absent from Bangka. Other species where found in our study sites, i.e. the common palm civet (Paradoxurus hermaphroditus), the Malay civet (Vivera tangalunga) and the small-toothed palm civet (Artogalidia trivirgata), but, from literature review, only the leopard cat is known to feed mainly on rats when available. We investigated the diet at community level and we did not detect no significant differences in frequency of occurrence (FO) or volume of small mammal's food items in the faeces of small carnivores between Bangka and Riau; however, we found that the importance of vegetal food items in the diet of small carnivores was greater (p=0.035) in Bangka (FO=51.1%) than in Riau, (FO=30.9%), thereby reflecting differences in predator community composition between both areas. Our results on small carnivore community composition, abundance and diet suggest that rat prey intake from this predator community would be less in Bangka plantations than in Riau. Prey-predators relationship in agricultural landscape is a complex issue. It is a challenge to determine if predation by a peculiar population or community, such as small carnivores, may be contingent to a low level ofprey, or may be a necessary factor to limit prey population. Broadly, our results suggest that barn owls cannot regulate rat population on their own, and that small carnivores probably play an important role, in the framework of a multi-factor hypothesis. Therefore, in a view to improve rat control, the producer should adapt agricultural practices and favor appropriate landuse in order to enhance small carnivores (notably leopard cats) within oil palm plantations. But many questions remain before to be able to give precise recommendations on this issue (Does rodenticide have the opposite effect to the one intended? How much does the leopard cat rely on forest habitat for survival in oil palm landscape? What would be the negative effects of leopard cat introduction on Bangka Island?. For more information on the land-use and habitat preference issue, another poster will investigate spatial distribution of small carnivores within oil palm plantations. (Texte intégral)