Tesi sul tema "Petit mammifère"
Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili
Vedi i top-18 saggi (tesi di laurea o di dottorato) per l'attività di ricerca sul tema "Petit mammifère".
Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.
Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.
Vedi le tesi di molte aree scientifiche e compila una bibliografia corretta.
Liang, Feifei. "Induction de l'expression génique par des petits ARN dans des cellules de mammifère". Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00684393.
Bouilloud, Marie. "Impact de l'anthropisation sur les liens entre les communautés de petits mammifères, leur microbiote et les dangers zoonotiques". Electronic Thesis or Diss., Montpellier, SupAgro, 2023. http://www.theses.fr/2023NSAM0029.
The increase in the emergence of zoonoses due to human activities is prompting us to refocus infectious diseases at the center of global concerns, by adopting a "One Health" approach. The integration of community ecology with epidemiology enables us to take into account all the ecological processes that influence both multiple hosts and multiple micro-organisms. By exploring the relationships between the latter in the transmission of zoonotic diseases, we could open up new perspectives for better prevention of zoonotic danger. Given the zoonotic risk posed by small mammals and the threat to their diversity posed by anthropization, we need to find new ways of managing these communities to limit the circulation of pathogens. In the long term, this would make it possible to establish strategies that benefit both biodiversity and health.The aims of this thesis were to understand the complex links between small mammal biodiversity, their microbiota and pathogens along an anthropization gradient. This included: i) monitoring the zoonotic hazard associated with small mammals in France, ii) understanding the links between small mammal biodiversity and the prevalence of multiple pathogens, in different environmental and management contexts, iii) examining the relationship between small mammal biodiversity and their microbiota, iv) analyzing the interactions between microbiota and pathogens.To this end, we sampled small mammal communities along a forest anthropization gradient, then performed serological and molecular analyses to detect and characterize zoonotic agents and gut microbiota. We then carried out statistical analyses and epidemiological modelling to understand the associations between zoonotic pathogens and microbiota, and their impact on the link between biodiversity and zoonotic danger.Along a gradient of anthropization, we have identified the presence of multiple pathogens in various rodent species, representing a real risk to public health. Anthropization has altered the composition and diversity of small mammal communities, as well as their microbiota. These changes have affected the relationship between biodiversity and pathogens. We found that unbalanced small mammal communities, with a higher abundance of competent species, were associated with an increased prevalence of pathogens. However, community management strategies such as deratting could have a counter-intuitive impact by reducing small mammal diversity and increasing pathogen circulation.The ecological mechanisms underlying microbiota composition varied according to species type, and seemed to play a crucial role in their resistance to anthropogenic disturbance. Furthermore, interactions between pathogenic and commensal microorganisms suggest that a host's susceptibility to a pathogen may be linked to the composition of its microbiota. With these results, new hypotheses emerge concerning the role of the microbiota in the competence of the host species and its susceptibility to pathogens.Thus, disturbances induced by various anthropogenic pressures can cause an imbalance in communities, which can alter the overall interactions between multiple hosts and micro-organisms, and consequently increase the circulation of pathogens. This underscores the importance of exploring new methods and approaches for a better understanding of these complex relationships between biodiversity, microbiota and public health, in particular by applying an integrated health approach
Aushana, Yonane. "Etude des réponses auditives dans le cortex occipital des mammifères aveugle de naissance". Paris 6, 2012. http://www.theses.fr/2012PA066348.
Labbé, Paul. "Utilisation de bandes boisées riveraines comme refuge par les petits mammifères dans la sapinière boréale". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq25624.pdf.
Paillat, Gilles. "Biodiversité dans les paysages agricoles : : approche fonctionnelle des peuplements et des populations de petits mammifères". Rennes 1, 2000. http://www.theses.fr/2000REN10008.
Mauffrey, Jean-François. "Biodiversité et écologie des communautés de rongeurs arboricoles et autres petits mammifères de Guyane française". Montpellier 2, 2002. http://www.theses.fr/2002MON20153.
Millan, de la Pena Norma angelica. "Effets de l'évolution des paysages agricoles sur les communautés animales (carabes et petits mammifères) : : approche pluri-échelle". Rennes 1, 2001. http://www.theses.fr/2001REN10133.
Croci, Solène. "Urbanisation et biodiversité : traits biologiques et facteurs environnementaux associés à l’organisation des communautés animales le long d’un gradient rural-urbain". Rennes 1, 2008. http://www.theses.fr/2008REN1S038.
In order to better understand urbanization impact on animals, we tried to identify the biological and environmental factors that influenced community organization along a rural-urban gradient. Specific composition of urban bird communities is very constant through various climatic areas. At a large scale, the town seemed to act as a filter selecting species on the basis of their biological traits. Structure of carabid beetles communities is mainly related to urban landscape fragmentation, those of bird and small mammal communities are mainly related to the quality of habitat patches. During the colonization process of woodlots from the rural landscape to the town centre, the structure of the communities is firstly influenced by the species capacity to move through the urban matrix and then, by the quality of habitat patches. These results can be used for the study of biological invasion process
Ringuet, Stéphane. "Evolution des peuplements et des populations de micromammifères terrestres de foret tropicale a la suite de la fragmentation de leur habitat : l'exemple du barrage de petit saut (Guyane française)". Paris, Muséum national d'histoire naturelle, 1998. http://www.theses.fr/1998MNHN0028.
Sansregret, Hugues. "Effets de l'éclaircie précommerciale sur les petits mammifères et les oiseaux forestiers dans la sapinière à bouleau blanc de l'Est". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0016/MQ55794.pdf.
Michel, Nadia. "AGRICULTURE ET BIODIVERSITÉ : APPROCHE PLURI-ÉCHELLE DE L'ÉVOLUTION D'UNE COMMUNAUTÉ DE PETITS MAMMIFÈRES ET DE DEUX RAPACES PRÉDATEURS LE LONG D'UN GRADIENT DE PAYSAGES AGRICOLES CONTRASTÉS". Phd thesis, Université Rennes 1, 2006. http://tel.archives-ouvertes.fr/tel-00097063.
Dans cette optique, nous nous sommes intéressés à une communauté de petits mammifères (rongeurs et insectivores < 40g) des haies dans trois paysages agricoles bretons contrastés du point de vue de l'intensité de l'usage des terres et de la densité des réseaux de haies, le long d'un gradient d'intensification de l'agriculture. Quatre axes principaux sont identifiés : (1) caractériser la structure et la composition de la communauté dans les trois paysages, (2) déterminer (dans une approche multi-échelle quelles sont les variables environnementales qui peuvent expliquer les
différences dans les assemblages d'espèces entre les haies, (3) caractériser les variations saisonnières de la communauté et des populations qui la composent en réponse à la dynamique des paysages. (4) Nous nous sommes aussi intéressés à un niveau trophique supérieur en comparant les abondances de deux espèces de prédateurs des petits mammifères, la buse variable (Buteo buteo) et la faucon crécerelle (Falco tinnunculus) en réponse à la composition des paysages et à la
disponibilité en proies.
Les résultats soulignent l'importance de développer des approches qui intègrent plusieurs niveaux d'organisation et plusieurs échelles d'analyse. La diversité, l'abondance, la composition, la biomasse et les amplitudes saisonnières de fluctuation de la communauté, ainsi que l'abondance des deux espèces de rapaces sont différentes entre les trois sites, montrant un effet de
l'intensification de l'agriculture sur les différents taxons étudiés. Le paysage, mais également les caractéristiques de l'habitat sont impliqués dans la structuration des assemblages d'espèces.
Ces résultats permettent d'envisager des modes de gestion et d'aménagement pour la conservation de la biodiversité dans les paysages agricoles.
Galal, Lokman. "Conséquences des invasions de rongeurs liées aux activités humaines sur l’épidémiologie et la structure des populations de Toxoplasma gondii : l'exemple du Sénégal". Thesis, Limoges, 2018. http://www.theses.fr/2018LIMO0036/document.
Toxoplasma gondii is a ubiquitous zoonotic protozoan capable of infecting all homeotherms including humans. A marked geographical contrast has been noted at the global scale concerning the genetic diversity and pathogenicity in humans of strains of this parasite. A growing number of studies show the importance of considering the influence of strain factor in the study of the epidemiology of human toxoplasmosis. However, genetic diversity data remain very limited for large regions of the world including Asia and Africa. Also, the determinants of the spatial structure of T. gondii populations worldwide remain poorly understood. During this work, we were interested in the influence of human exchanges on the evolution of parasite populations in Africa, and more particularly in Senegal. Our results support an important role of invasive rodents that accompany human exchanges in the introduction of strains at the port areas of the country through maritime trade. Our results also suggest a role of the invasive mouse Mus musculus domesticus in the counterselection of the clonal lineage Africa 1, the predominant lineage of T. gondii in West Africa. These new elements shed light on some of the mechanisms that shape T. gondii populations. Further studies in different epidemiological situations, combined with experimental studies, will be needed to accurately measure the influence of these host parasite interactions on the epidemiology of toxoplasmosis
Sarem, Mahrou. "Identification dans les sérums de mammifères de peptides (MW< 1000 DA) à activité mitogénique : influence de ces peptides sur les activités biologiques des IGF1 et IGF2". Nancy 1, 2000. https://hal.univ-lorraine.fr/tel-01746897.
Laudet, Frédéric. "Caractérisation taphonomique des gisements oligocènes karstiques à petits vertébrés fossiles des phosphorites du Quercy (SW France)". Montpellier 2, 2000. http://www.theses.fr/2000MON20086.
Gagné, Nancy. "Comparison of the effects on small mammals of regeneration methods in the boreal balsam fir forest, Comparaison des effets sur les petits mammifères des méthodes de régénération de la sapinière boréale". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq25408.pdf.
Fernandez, Garcia Monica. "Late Pleistocene palaeoenvironmental reconstruction of Northeastern Iberia : taxonomic, taphonomic and isotopic approach based on small-mammal assemblages". Thesis, Paris, Muséum national d'histoire naturelle, 2019. http://www.theses.fr/2019MNHN0010.
The main objective of the PhD thesis is the reconstruction of palaeoenvironment experienced during the Late Pleistocene, mainly during Marine Isotope Stage 3 (MIS 3), at northeastern Iberia, through the combination of different ecological approaches based on small-mammal assemblages (insectivores, bats and rodents). Three archaeological sites are included: Abric Romaní rock-shelter (Capellades, Barcelona); Teixoneres cave (Moià, Barcelona) and Arbreda cave (Serinyà, Girona). It is also included a paleontological site from a close chronology, Xaragalls cave (Vimbodí-Poblet, Tarragona). The aim is the integration of the available data of the studied archaeological sequences through palaeoecological and oxygen isotope compositions analysis for increasing our knowledge about the MIS 3 environment from a regional point of view and reach a better understanding of the climatic singularities of Iberia during last Neanderthals settlements. One of the focus is fixed in oxygen isotope compositions (δ18O) analyzed from enamel tooth phosphates of both modern and fossil rodent remains of these localities. Taphonomic and taxonomical analyses based on small-mammals are also performed to reach a complete ecological interpretation of these sites. Other methods currently use in palaeoenvironmetal reconstructions based on small-mammal assemblages were also employed, such as mutual ecogeographic range method, habitat weighting method, chorotypes classification and bioclimatic model method. Considering the isotopic results obtained, this work shows that two main factors should be considered in Iberian palaeoenvironmental reconstructions: the possible seasonality of the rodent assemblages, derived from the predator, and the regional particularities on δ18O values of meteoric waters in the Iberian Peninsula. Accordingly, a new methodological proposal for the reconstruction of palaeotemperatures from rodent tooth δ18O accumulated in the Iberian Peninsula was developed and after applied to the archeological and paleontological sites studied. The recorded palaeoenvironment show globally cooler and wetter conditions than nowadays but it is detected notable climatic stability in all sites, with only slight changes related to stadial-interstadial pulsations, reflected mainly in oscitations between Mediterranean and mid-European species abundances. Woodland formations are always abundant throughout the sequences. The continuous maintenance of woodland covertures besides slight climatic variations and globally stable rodent communities, demonstrate the singularities of Iberian Peninsula, in contrast to the high climatic instability experience in Eurasia. This work highlights that a combination of different local-scale palaeoecological proxies compared to larger-scale proxies is essential to obtain faithful environmental reconstructions
Morilhat, Céline. "Influence du système sol - végétation - pratiques agricoles des prairies franc-comtoises sur la dynamique de population de la forme fouisseuse du campagnol terrestre (arvicola terrestris scherman shaw, 1801)". Phd thesis, Université de Franche-Comté, 2005. http://tel.archives-ouvertes.fr/tel-00341535.
Gomard, Yann. "Relations hôtes – parasites zoonotiques : diversité, aspects évolutifs et implications épidémiologiques. Le cas de la leptospirose dans les îles du sud-ouest de l’océan Indien". Thesis, La Réunion, 2015. http://www.theses.fr/2015LARE0029/document.
Leptospirosis is considered as the most widespread zoonosis worldwide but the incidence levels are higher in tropical regions and particularly on islands. The South-Western Indian Ocean islands are no exception and the disease is of major medical concern in several islands notably in Seychelles, displaying some of the highest human incidence ever reported. Based on available data, the human epidemiology appears contrasted in the region: on Mayotte, human cases result from the infection with four distinct Leptospira species whereas on Reunion Island or Seychelles, a single species causes the majority of clinical cases. The main objective of this thesis is to identify some of the drivers of this singular epidemiology. We first completed the information available on this human disease in the region by investigating the leptospirosis situation in the Union of the Comoros, a country where no autochthonous transmission has been reported so far. Our results indicate that Comorian populations are exposed to Leptospira, which are antigenically comparable to those detected in the neighbouring island of Mayotte. This finding suggests that the apparent absence of leptospirosis in some islands rather reflects a lack of surveillance. We then investigated the genetic diversity of Leptospira on distinct islands home to distinct endemic animal species that may shed distinct Leptospira lineages and thus at least in part explain the contrasted epidemiology of leptospirosis in the region. Specifically, we describe a high diversity of pathogenic Leptospira within Malagasy bats (Chiroptera) and further show that Leptospira diversity is not structured by geography. Instead, we show that these Leptospira display a strong specificity towards their hosts, which may result from different evolutionary processes including co-speciation and host switching. Using this tight host specificity, we investigated the leptospirosis epidemiology on Mayotte, where we show that the important bacterial diversity reported in clinical cases is due of the presence of several distinct animal species acting as reservoirs, some of which introduced from the neighbouring Madagascar. Altogether, results presented herein combined to data produced by our lab suggest that the epidemiology of leptospirosis in the SWOI results from distinct assemblages of cosmopolitan and autochthonous/endemic Leptospira. Keywords : Leptospirosis, Leptospira, Chiroptera, small mammals, hosts-parasites associations, MAT, MLST, co-phylogeny, Madagascar, Mayotte, Union of Comoros, South-Western Indian Ocean