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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Efficacy of an Electronic Scarecrow on 4 Mammalian Crop-Raiders in Limpopo Province, South Africa

Richardson, Merrie Renee 01 August 2014 (has links)
In South Africa, 2 primate species, Chacma baboons (Papio ursinus) and vervet monkeys (Chlorocebus pygerythrus), and 2 nocturnal mammals, Cape porcupine (Hystrix africaeaustralis) and bushbuck (Tragelaphus scriptus), are among many species of crop raiders. Currently, cost-effective, non-lethal solutions are lacking. From June through December 2012, I installed novel electronic scarecrows on two commercial citrus orchards and a private reserve and used video-recording remote cameras to assess cropraiders’ reactions to them in Limpopo Province, South Africa. I used focal animal sampling data from treatment and control group animals to examine differences in activity budgets and behaviors of interest between groups. Compared to animals at sites with an inactive or no scarecrow, I hypothesized that animals in the treatment group would have altered activity budgets and rates of behaviors; that they would forage or feed less, run more (as a result of being frightened), be more vigilant and thus scan their surroundings more often, and display a visible startle in response to stimuli from scarecrows. Bushbuck at treatment sites spent a larger proportion of their activity budget running, and were more often startled. However, foraging was never observed, and bushbuck in the control group scanned their surroundings more often. Porcupines at treatment sites spent a larger portion of their activity budget running, though foraging was only observed in 1 control group animal and looking was never observed. For primates, treatment (control, scarecrow) was meaningful in explaining differences in focal animal activity budgets of baboons (F = 5.49, P = 0.001) and vervet monkeys (F = 7.09, P = 0.001) as indicated by a permutational MANOVA in R. In baboons, treatment was positively correlated with running; ratios of baboons that ran to baboons that did not run differed between treatment groups (G = 15.78, P < 0.001). Treatment was negatively correlated with feeding; ratios of baboons that fed or foraged to baboons that did not feed or forage differed (G = 5.39, P = 0.02). Significant differences between groups of vervet monkeys were not found with G-tests for the same behaviors of interest. Electronic scarecrows are promising tools for human-wildlife conflict mitigation, particularly for nocturnal antelopes. For primates, further innovation in design of scarecrows to incorporate a visual stimulus is recommended.
192

Object permanence in orangutans, gorillas, and black-and-white ruffed lemurs

Mallavarapu, Suma 13 May 2009 (has links)
This study examined object permanence in Sumatran orangutans (Pongo abelii), Western lowland gorillas (Gorilla gorilla gorilla), and black-and-white-ruffed lemurs (Varecia variegata) at Zoo Atlanta. A literature review reveals two main issues with object permanence research in non-human primates. One of the issues is that it is difficult to make valid comparisons between different species because very few studies have been conducted using appropriate controls. Thus, one of the goals of this study was to conduct control trials for all tasks in the traditional object permanence test battery, in order to reliably assess and compare performance in the species under study. The second issue is concerned with the finding that all of the non-human primate species tested so far have failed one of the more difficult tasks in the test battery, namely the non-adjacent double invisible displacement task. It has been hypothesized that this performance limitation is a result of the manner in which the task is presented. Thus, the second goal of this study was to modify the existing methodology and present the task to gorillas and orangutans in locomotive space to see if performance improves. This is the first study to present this task to non-human primate species in locomotive space. This study found that orangutans were the only species to reliably pass most tasks in the traditional object permanence test battery. Black-and-white ruffed lemurs failed most visible and invisible displacement tasks. Owing to the small sample size of gorillas in this study, further research is required before any firm conclusions can be made about the ability of this species to solve visible and invisible displacement tasks in the traditional object permanence test battery. Presenting the boxes in locomotive space to gorillas and orangutans did not improve performance on the non-adjacent double invisible displacement task. Further research is required to resolve the question of whether this performance limitation is a result of the manner in which the task was presented.
193

Contribution à la caractérisation moléculaire et cellulaire des chimères YF-17D / Dengue dans le cadre du développement préclinique du vaccin Dengvaxia® / Contribution to the molecular and cellular characterization of YF-17D/Dengue chimera as part of the preclinical development of Dengvaxia® vaccine

Mantel, Nathalie 08 March 2018 (has links)
Sanofi Pasteur travaille depuis plus de 20 ans au développement d’un vaccin contre la Dengue, maladie virale pouvant présenter des formes sévères. Ce vaccin, dénommé Dengue CYD est composé de quatre virus recombinants basés sur la souche vaccinale contre la Fièvre Jaune dans laquelle les gènes codant les protéines prM et E ont été remplacés par ceux des différents sérotypes de virus Dengue.Dans les études décrites ici, nous avons démontré la stabilité génétique des souches vaccinales au cours des étapes de production, et nous avons mis au point un système de qRT-PCR pour quantifier le génome viral afin de caractériser les lots et suivre les virémies post-vaccinales.De plus, différentes études précliniques menées chez le macaque ont permis :1) d’évaluer l’immunogénicité du vaccin après immunisation par différentes formulations vaccinales et selon différents schémas visant à réduire les interférences entre les sérotypes. L’administration de vaccins bivalents complémentaires à des sites anatomiques différents ou de façon séquentielle, l’établissement d’une pré-immunité hétérologue, une moindre dose relative du sérotype vaccinal dominant ou l’administration d’un rappel à un an ont ainsi permis de mettre en évidence des pistes d’amélioration du schéma vaccinal.2) d’évaluer la biodistribution et l’excrétion du vaccin afin de confirmer son innocuité.3) de tester la neutralisation d’un panel de souches virales par des sérums des singes vaccinés pour montrer que les anticorps induits par le vaccin peuvent neutraliser des souches Dengue circulantes d’origines géographiques et de génotypes variés.Enfin, l’absence de risque de dissémination du virus dans l’environnement via les tiques, arthropodes vecteurs d’autres Flavivirus, a été confirmée.Ces études ont permis d’apporter des éléments démontrant l’intérêt du vaccin Dengue CYD pour lancer des études cliniques et compléter les dossiers réglementaires visant à l’enregistrement du vaccin Dengvaxia® / Sanofi Pasteur has been working for more than 20 years to develop a vaccine against Dengue, viral disease that can cause life-threatening forms. The CYD Dengue vaccine is a tetravalent recombinant virus based on Yellow fever vaccine strain in which genes encoding prM and E proteins have been replaced by the corresponding genes from the different Dengue virus serotypes.In the studies described here, we demonstrated the genetic stability of the vaccine strains during the manufacturing steps and we set-up a qRT-PCR system to quantify viral genome in order to characterize batches and to follow post-vaccination viremia.In addition, different pre-clinical studies were conducted in macaques in order:1) To evaluate the vaccine immunogenicity after immunizations according to different schedules and formulations aiming at decreasing interferences between serotypes. Different parameters were shown to improve vaccine immunogenicity, such as administration of complementary bivalent vaccines at separate anatomical sites or sequentially, establishment of a heterologous pre-immunity, adaptation of the formulation by decreasing the dose of the dominant serotype or administration of a 1-year booster.2) To evaluate the biodistribution and shedding of the vaccine to confirm its safety3) To test neutralization by vaccinated-monkey sera of a panel of circulating viral strains to demonstrate that antibodies elicited by the vaccine should neutralize Dengue strains from different geographical origins and genotypesFinally, the absence of risk of dissemination of the virus in the environment via ticks, i.e. arthropods responsible for transmission of other Flaviviruses, was confirmed.These studies brought elements demonstrating the interest of the CYD Dengue vaccine to allow starting clinical trials and filing of technical dossiers supporting Dengvaxia® submission and registration
194

Recherche et caractérisation des virus entérotropes excrétés par les primates d'Afrique Centrale / Research and characterization of enteric viruses excreted by primates of Central Africa

Mombo, Illich Manfred 10 December 2015 (has links)
Les virus entérotropes sont des virus ubiquitaires infectant une large catégorie de vertébrés dont l’homme et les primates non-humains (PNHs). Ils se transmettent principalement par voie féco-orale directe ou indirecte à la suite de laquelle ils atteignent les entérocytes et s’y multiplient. Bien que parfois asymptomatiques, les infections causées par les virus entérotropes peuvent se manifester par des gastroentérites très fréquentes chez les enfants de moins de 5 ans. Ces mêmes virus peuvent être responsables de pathologies sévères telles que les maladies respiratoires, encéphalitiques, cardiaques, neurologiques. À partir des années 1950, de nombreux virus entérotropes ont été isolés de tissus de PNHs couramment utilisés en cultures cellulaires et en recherche biomédicale. Dès lors, de nombreuses études ont été conduites sur la caractérisation des virus entérotropes principalement chez les PNHs captifs ou en contact avec l’homme. En milieu naturel, en dehors des entérovirus et des adénovirus, leur circulation, leur épidémiologie et leur diversité restent encore peu connues. L’objectif de cette thèse est donc de rechercher et caractériser les virus entérotropes chez les PNHs d’Afrique Centrale. Ainsi à partir de 600 échantillons de fèces de PNHs collectés dans des forêts et réserves naturelles au Gabon, nous avons pu mettre en évidence la circulation de différentes espèces d’entérovirus (EVs) chez les mandrills et les chimpanzés. Cette caractérisation a également permis de mettre en évidence des EVs proches d’EVs infectant l’homme ainsi que deux nouveaux sérotypes chez un chimpanzé et chez un mandrill. Nous avons également mis en évidence un astrovirus (AstV) totalement divergent d’AstVs référencés chez un gorille. En dehors de leur circulation en milieu naturel, les virus entérotropes sont également présents chez les PNHs en contact fréquents avec l’homme. De ce fait à partir d’échantillons fécaux d’un groupe de 12 chimpanzés du Sanctuaire de Tchimpounga, nous avons caractérisé l’EV-C99 responsable de cas de paralysie chez l’homme et probablement responsable de celle observée chez un chimpanzé. De plus, deux sapovirus (SaVs) très proches d’un SaV identifié chez l’homme ont également été caractérisés. L’Afrique Centrale est donc caractérisée par une diversité de virus entérotropes qui circulent chez les PNHs. L’identification chez les PNHs de virus entérotropes proches en milieu naturel de ceux infectant l’homme soulève l’existence d’une probabilité de transmission inter-espèce entre les PNHs et l’homme dont le sens reste encore à déterminer. Par contre chez les PNHs du sanctuaire, la susceptibilité à ces virus humains peut être responsable de pathologies graves comme la paralysie observée chez les chimpanzés. / The enteric viruses are ubiquitous virus infecting a broad range of vertebrates, including humans and non-human primates (NHPs). They are spread by direct or indirect fecal-oral route following which they reach the enterocytes and multiply. Even though infections caused by these viruses are asymptomatic, enteric viruses could be responsible for frequent gastroenteritis in children under 5 years of age. These viruses may be responsible for severe pathologies such as respiratory, encephalitic, cardiac and neurological diseases. In the 1950s, many viruses have been isolated from NHPs species commonly used in cell culture and biomedical research. Since, many studies have been conducted to characterize, then enteric viruses have been mainly identified in captive NHPs or those living in close contact with humans. Little is known concerning the circulation, epidemiology and diversity of enteric viruses in the wild, except for enteroviruses and adenoviruses. The objective of this thesis is to investigate and characterize the enteric virus in NHPs of Central Africa. Thus from 600 samples of feces of NHPs collected in natural forests and reserves in Gabon, we highlighted the circulation of different species enteroviruses (EVs) in mandrills and chimps. We also identified EVs close to those infecting humans as well as two new serotypes in a chimpanzee and in a mandrill. We have highlighted an astrovirus (AstV) completely divergent from those referenced in a gorilla. Apart from their outstanding natural environment, enteric viruses are also present in NHPs in frequent contact with humans. Therefore fecal samples from a group of 12 chimpanzees from the Tchimpounga Sanctuary, we characterized the EV-C99 responsible for cases of paralysis in humans and probably responsible for that observed in a chimpanzee. In addition, two sapovirus (SaVs) very close to a SaV identified in humans have also been characterized. Central Africa is therefore characterized by a diversity of enteric virus circulating in NHPs. The identification in the wild of enteric virus in NHPs close to those infecting humans raises probability of cross-species transmissions between NHPs and humans whose sense remains to be determined. However in NHPs in the sanctuary, susceptibility to these human viruses can be responsible for severe diseases such as paralysis observed in chimpanzee.
195

Ecologia alimentar e comportamento de Callicebus nigrifrons em um fragmento florestal de Mata Atlântica em Campinas, SP / Feeding ecology and behavior of Callicebus nigrifrons in an Atlantic Forest fragment in Campinas, SP

Nagy-Reis, Mariana Baldy, 1986- 20 August 2018 (has links)
Orientadora: Eleonore Zulnara Freire Setz / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T18:01:50Z (GMT). No. of bitstreams: 1 Nagy-Reis_MarianaBaldy_M.pdf: 70885205 bytes, checksum: c47da08b5a6303f670a2ad95f9faf467 (MD5) Previous issue date: 2012 / Resumo: O gênero Callicebus é o segundo maior dentre os primatas neotropicais e possui ampla distribuição geográfica. No entanto, também e um dos gêneros menos estudados e pouco se sabe sobre sua ecologia e comportamento. Dessa forma, estudamos a ecologia alimentar e o comportamento de C. nigrifrons, com ênfase na dieta, padrão de atividade, uso de espaço e estratégias adotadas em resposta a abundancia de recursos no ambiente. Observações sistemáticas de um grupo de sauás foram conduzidas ao Iongo de um ano (547hs) em um fragmento de Mata Atlântica em Campinas, SP...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: Callicebus is the second largest genus among neotropical primates and is widely distributed. However, it is also one of the less-studied genera and there is little information on its ecology and behavior. Therefore, we studied the feeding ecology and behavior of C. nigrifrons, focusing on its diet, activity pattern, use of space, and strategies in response to food abundance. Information was collected during systematic observations on a titi monkey group during a one-year period (547hs) in an Atlantic Forest fragment in Carnpinas, SP...Note: The complete abstract is available with the full electronic document / Mestrado / Ecologia / Mestre em Ecologia
196

Adaptive radiations and ecological diversity of primates during the early Tertiary / Radiations adaptatives et diversité écologique des primates au début du Tertiaire

Ramdarshan, Anusha 10 November 2011 (has links)
Juste après son apparition au début de l'Ère Tertiaire, l'ordre des Primates connaît plusieurs phases de diversification intenses. Ces épisodes successifs sont à l'origine de l'émergence des groupes actuels. Malgré l'importance de ces évènements, leurs modalités restent peu connues, particulièrement l'importance des facteurs écologiques. En Europe et en Amérique du Nord, la transition Paléocène-Éocène est marquée par un réchauffement climatique majeur. C'est à cette époque que les primates modernes (Euprimates) apparaissent, se dispersent, et se diversifient de manière explosive au cours de l'Éocène. Ce travail a pour objectif de caractériser l'émergence de cette diversité à travers les facteurs écologiques tels que le partage des ressources, les phénomènes de compétition, et les changements paléoenvironnementaux. Dans ce but, l'étude de la structure des dents et des micro-usures laissées par le bol alimentaire permet la reconstruction du régime alimentaire des primates paléogènes (Adapiformes, Omomyiformes, Anthropoidea et Plesiadapiformes), l'un des meilleurs indicateurs de l'écologie d'un animal.En Europe, les premiers euprimates (e.g., Donrussellia [adapiformes]), bien qu'ayant un patron dentaire de type insectivore, étaient majoritairement frugivores et secondairement insectivores. Ils occupaient ainsi des niches distinctes des plésiadapiformes (folivores, frugivores et gommivores). La diversification des euprimates au cours de l'Éocène a conduit à l'augmentation des pressions de compétition au sein des communautés et à l'apparition de spécialisations écologiques. Par exemple, les adapinés, initialement frugivores, ont montré une évolution de leur régime alimentaire par l'intégration de feuilles et d'objets durs.En Asie, l'étude des communautés fossiles a mis en exergue une forte pression de compétition entre les formes de petite taille (éosimiidés, tarsiidés, adapidés), qui avaient tous un régime alimentaire à base de fruits et d'insectes. Les anthropoïdes asiatiques (amphipithècidés) montrent des spécialisations écologiques très singulières avec notamment un régime alimentaire à base d'objets durs. En Afrique, les communautés éocènes témoignent d'une diversité importante, avec la colonisation des niches insectivores (adapiformes), frugivores (adapiformes, strepsirhiniens et anthropoïdes) et folivores (adapiformes, anthropoïdes).Cette étude a mis en exergue la diversité et la variabilité du régime alimentaire qui peut exister pour une espèce donnée (actuelle ou fossile) en fonction des facteurs biotiques (compétition) et abiotiques (environnement, géographie). La comparaison entre les différents continents montre que les primates (adapiformes, omomyiformes et anthropoïdes) n'occupaient pas les mêmes niches écologiques au sein des différentes communautés. Ces différences au niveau du partage des ressources et des phénomènes de compétition se sont répercutées sur la dynamique des différentes radiations. / Soon after its appearance at the beginning of the Tertiary, the Primate order underwent several successive episodes of diversification which were the basis for the emergence of the higher taxonomic groups that can be observed in nature today. Despite the importance of these events, little is known regarding the factors that governed them, in particular the importance of the ecological factors involved. The Paleocene-Eocene transition in North America and Europe was marked by a period of major global warming. It was during this time that modern primates (Euprimates) appeared and dispersed before experiencing an explosive diversification throughout the Eocene. This study aims to characterize the emergence of this diversity through the identification of ecological factors, such as environment, resource partitioning and competition. In this framework, the study of dental structure and of dental microwear is used to reconstruct the diet of Paleogene primates (Adapiformes, Omomyiformes, Anthropoidea and Plesiadapiformes), one of the best indicators of the ecology of a given animal. In Europe, although exhibiting a dental morphology better suited to insect-eating, the first euprimates (e.g., Donrussellia [adapiformes]) were fruit-eaters, only supplementing their diet with insects. They mostly occupied different niches to co-occurring plesiadapiforms (leaf-, fruit- and gum-eaters). The diversification of euprimates led to the increasing competition among primate communities and to the apparition of different dietary specializations. For example, Adapines, initially having a diet based on fruit, show a dietary shift by incorporating leaves and harder objects in their diet.In Asia, the study of fossil primate communities has highlighted resource partitioning and competition among small-bodied primates (eosimiids, tarsiids, and adapids), which all had a diet based on fruit and insects. Asian anthropoids (amphipithecids) show some singular ecological specialization towards sclerocarpic foraging.In Africa, Eocene primates show a high diversity, with the colonisation of numerous ecological niches such as insect-eating (adapiformes), fruit-eating (adapiformes, strepsirhines and anthropoids) et leaf-eating (adapiformes, anthropoides).This study highlights dietary diversity and variability which can exist for a given primate (extant or fossil) according to factors which can be biological in nature (i.e., competition) or not (i.e., environment, geography). The comparison between the different continents demonstrates that primates (Adapiformes, Omomyiformes, and Anthropoidea) occupied different niches in different primate communities. These differences in resource partitioning and competition are most probably reflected in the different paths these adaptive radiations took.
197

Identificación de especies de Plasmodium en base al gen codificante 18S ARNr en muestras de sangre de primates no humanos en cautiverio

Ochoa Montes, Yeni Karen January 2018 (has links)
Publicación a texto completo no autorizada por el autor / Identifica genéticamente a especies de Plasmodium en base al gen que codifica la subunidad 18S ARNr en muestras de sangre de primates no humanos en cautiverio. El diseño de este estudio es observacional y transversal. Esta investigación es un estudio secundario en el que se usa muestras biológicas e información de un grupo de primates no humanos entre adultos, jóvenes y crías de ambos sexos pertenecientes al género Saimiri y Lagothrix evaluados durante los años 2011 y 2012 en algunas ciudades de Perú. El análisis es realizado mediante el software MEGA v6.0 y el programa Excel. Se realiza análisis descriptivo de las variables de las pruebas ensayadas usando los siguientes métodos: evaluación microscópica por gota gruesa, técnicas moleculares de PCR para confirmar la infección y secuenciamiento del gen 18S ARNr. Se encuentra que el 7.05 % (6/85) de primates no humanos están infectados con Plasmodium spp. En base al secuenciamiento y análisis filogenético molecular del gen 18S ARNr se observa infección por Plasmodium brasilianum en una muestra de primate Lagothrix lagotricha y por Plasmodium malariae en cuatro muestras de primates Saimiri sciureus. Concluye que los parásitos identificados en las muestras de estudio son Plasmodium malariae y Plasmodium brasilianum, este último previamente reportado como especie que infecta a primates no humanos del Nuevo Mundo. / Tesis
198

Estudo morfológico do hipocampo de uma espécie de primata da Amazônia: Cebus apella, (Linnaeus, 1758) / Anatomic study of the hippocampus in a primate species of the Amazon Cebus apella (Linnaeus, 1812)

Torres, Laila Brito [UNIFESP] 24 November 2010 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-11-24 / Os primatas constituem modelos animais insubstituíveis para áreas de investigação científica devido a sua estreita relação evolutiva com os seres humanos o que assegura modelos de alta fidelidade com capacidade preditiva e discriminativa que podem não estar disponíveis em outras espécies. O Cebus apella, uma espécie de primata do novo mundo que pertence à família Cebidae, subordem Cebinae (Linnaeus, 1758), são comumente usados em pesquisas biomédicas e comportamental sendo uma espécie eleita para muitos modelos experimentais com enfoque cognitivo. O hipocampo, estrutura límbica altamente plástica situado no lóbulo temporal é importante para a aprendizagem e consolidação da memória. Desta forma, o objetivo deste estudo foi caracterizar quantitativamente e qualitativamente as células parvalbumina-positivas no hipocampo de Cebus apella, bem como estimar o volume e o número de neurônios em seus diferentes subcampos, utilizando o método do fracionador óptico. Os resultados obtidos em nosso estudo podem ser úteis para diversos projetos experimentais que tenham como foco a medicina translacional. / The nonhuman primates constitute irreplaceable animal models for research areas in which their close evolutionary relationship to humans ensures high fidelity models with predictive and discriminative abilities that may not be available in other species. The Cebus apella, a New World primate specie belonging to the Cebidae family, Cebinae suborder (Linnaeus, 1758) are commonly used in biomedical and behavior research being the specie of choice for many cognitive experimental tasks. The hippocampus, a highly plastic limbic structure situated in the temporal lobe is important for learning and memory consolidation. In this way, the aim of this study was to characterize quantitatively and qualitatively the Parvalbumin positive cells in the hippocampal formation of the Cebus monkey and also estimate the volume and neuronal number in their different subfields using an optical fractionator design method. The results obtained in our study will be useful for many experimental designs in translational medicine. / TEDE / BV UNIFESP: Teses e dissertações
199

Uso de diferentes fitofisionomias por macacos-prego-do-peito-amarelo Sapajus xanthosternos Wied-Neuwied 1820 em fragmento de Mata Atlântica, Sergipe, Brasil

Sousa, Saulo Meneses Silvestre de 29 July 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Capuchin monkeys are frugivorous-insectivorous primates, although they can explore a wide range of food items. The availability of fruits is a key-aspect of the ecology of these primates, with direct influences over the quality of a given area for the species, and often represents the main determinant of the pattern of range use of groups. In a population-level analysis, however, the pattern of occupation of a fragment by capuchin monkeys is influenced by a broader set of factors, including structural parameters of the habitat. The purpose of this study was to describe the pattern of use of different phytophysiognomies by a population of yellow-breasted capuchins in an Atlantic Forest fragment, relating to the structural aspects and fruit availability of the environment. The study area is in Itaporanga D'Ajuda (11º08'07 "S, 37º18'43" W), in the state of Sergipe, henceforth denoted by Fazenda Rio Fundo (FRF). The fragment has approximately 800 ha of native forest, associated with surrounding plantations of Eucalyptus sp. and bamboos. Among the native forest formations, the vegetation types of shrub-arboreal Restinga (RE), Mata de Tabuleiro (MT), and arboreal Restinga (mature, FM, and secondary, FS). Data collection was carried out monthly between March 2015 and February 2016. The different habitat types of the FRF were compared in relation to the availability of fruits, through phenological monitoring of tree species; and habitat structure, by analyzing its medium height, DBH, density, land cover rate and species composition of the tree community. The use of different habitats by capuchin monkeys, and the occurrence of potential predators of the species, was monitored using 31 camera traps, distributed among habitats. The FM and the FS are the habitats with greater height of canopy and ground cover rate at FRF, in addition to having a pattern of relatively continuous availability of fruit throughout the year. The areas of RE and MT, in turn, are the habitats with the highest dominance indexes in the plant community, as well as the most open and seasonal ones. From a sampling effort of 1,444 trap-day, capuchin monkeys were recorded in 430 videos in 39 separate visits. Nine of the 10 permanent sampling points in FM or FS received visits of the target-species. No record of the presence of monkeys was obtained in MT or RE. We observed that the areas of FM and FS represent preferential habitats for the yellow-breasted capuchins at FRF. This preference is related to the greater height of canopy and ground cover rate of these areas. The advantages conferred by these parameters refer to both the availability of food and support for the locomotion of the primates, and thus, protection against predation. The main threat faced by the population of S. xanthosternos at FRF refers to its limited size, which in turn, stems from the small size and high degree of isolation of the fragment. The presence of several small remaining fragments in the region, however, enables the creation of ecological corridors, which would increase the total area available for the maintenance of the yellow-breasted capuchins, contributing to the conservation of populations of the species in the state. / Macacos-prego são considerados frugívoros-insetívoros, apesar de explorarem uma vasta gama de recursos alimentares. A disponibilidade de frutos é um aspecto-chave da ecologia desses primatas, influenciando diretamente na qualidade da área para as espécies, além de frequentemente ser o principal determinante do padrão de uso da área de vida dos grupos. Numa análise em nível populacional, entretanto, o padrão de ocupação de um fragmento por macacos-prego pode ser influenciado por um conjunto mais amplo de fatores, o que inclui parâmetros estruturais do habitat. O objetivo do presente trabalho foi descrever o padrão de uso de diferentes fitofisionomias por uma população de Sapajus xanthosternos num fragmento de Mata Atlântica, relacionando-o a aspectos estruturais e de disponibilidade de frutos do ambiente. A área de estudo fica no município de Itaporanga D’Ajuda (11º08’07”S, 37º18’43”W), no estado de Sergipe, doravante tratado por Fazenda Rio Fundo (FRF). O fragmento possui cerca de 800 ha de floresta nativa, associados a plantações de Eucalyptus sp. e bambus. Entre as formações florestais nativas, estão as fitofisionomias de Restinga arbustivo-arbórea (RE), Mata de tabuleiro (MT), e Restinga arbórea madura (FM) e secundária (FS). A coleta de dados foi realizada mensalmente entre março de 2015 e fevereiro de 2016. Os diferentes tipos de habitat da FRF foram comparados entre si em relação à disponibilidade de frutos, através do monitoramento fenológico de espécies arbóreas; e à sua estrutura, através da análise de seus valores médios de altura, DAP, densidade, taxa de cobertura do solo e composição florística de indivíduos arbóreos. A utilização dos diferentes tipos de habitat pelos macacos-prego, além da ocorrência de potenciais predadores da espécie, foi monitorada através de 31 armadilhas fotográficas, distribuídas entre os habitats. A FM e a FS são os habitats com maior altura de dossel e taxa de cobertura do solo da FRF, além de apresentarem um padrão de disponibilidade de frutos relativamente contínuo ao longo do ano. As áreas de RE e MT, por sua vez, são os habitats com os maiores índices de dominância na comunidade vegetal, e também os mais abertos e sazonais da FRF. De um esforço amostral de 1.444 armadilhas-dia, o macaco-prego foi registrado em 430 vídeos, em 39 visitas independentes. Nove dos 10 pontos amostrais fixos em FM ou FS receberam visitas da espécie-foco. Não foi obtido nenhum registro da presença dos macacos em MT ou em RE. Foi observado que na FRF as áreas de FM e FS representam habitats preferenciais para os macacos-prego-do-peito-amarelo. Essa preferência parece estar relacionada à maior altura de dossel e taxa de cobertura do solo dessas áreas. As vantagens conferidas por esses parâmetros referem-se tanto à disponibilidade de alimento, com à de suportes para a locomoção dos macacos e, por conseguinte, proteção contra predação. A principal ameaça enfrentada pela população de S. xanthosternos da FRF refere-se ao seu tamanho limitado que, por sua vez, decorre do tamanho reduzido e alto grau de isolamento do fragmento. A presença de vários pequenos fragmentos remanescentes na região, entretanto, possibilita a criação de corredores ecológicos, o que aumentaria a área total disponível para a manutenção do macaco-prego-do-peito-amarelo, colaborando para a conservação das populações da espécie do estado.
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Rôles relatifs des facteurs démographiques, sociaux et sélectifs sur la sélection de partenaires reproducteurs chez le gorille des plaines de l'ouest / Relative roles of demographic, social, and selective factors in breeding partner selection in western lowland gorillas

Baudouin, Alice 21 December 2017 (has links)
Chez de nombreuses espèces, il a été montré que les stratégies de choix de partenaires socio-sexuels par un individu étaient liées aux qualités de ces partenaires (phénotypiques ou génétiques) et étaient susceptibles de maximiser la qualité de ses descendants et améliorer sa propre valeur adaptative. Nous nous sommes intéressés au choix de partenaires chez les femelles de gorille de plaines de l’ouest par une étude de leur dispersion sociale en lien avec l’influence relative de l’environnement social et des caractéristiques des mâles adultes dans les décisions des femelles à résider dans un groupe social ou à émigrer, et dans leur choix du groupe dans lequel immigrer. Nous avons montré que les femelles immigrent préférentiellement dans des groupes reproducteurs plutôt que vers des mâles solitaires et vers des groupes jeunes plutôt que vieillissants. Les groupes de 10-15 individus sont évités. Les femelles émigrent des groupes contenant une grande proportion d’individus affectés par une maladie de peau. A court terme après un effondrement démographique du à une épidémie à virus Ebola, le taux d’émigration des femelles diminue dans les groupes de grande taille, ce qui suggère une meilleure qualité reproductrice et protectrice des mâles survivants. Les caractéristiques génétiques des partenaires sexuels dans le choix des femelles, notamment les gènes du complexe majeur d’histocompatibilité (CMH) qui codent pour des protéines impliquées dans les défenses immunitaires, peuvent être impliquées dans le choix de partenaire chez certains primates. Son implication éventuelle n’avait jamais été étudiée chez le gorille. Dans cette perspective nous avons cherché à développer une méthode pour étudier ce complexe de gènes à partir d’échantillons d’ADN non invasifs (fèces), c’est-à-dire avec de l’ADN faiblement concentré et dégradé. Nous avons défini une nouvelle amorce puis utilisé des méthodes de séquençage haut débit, d’électrophorèse sur gel à gradient dénaturant et un marqueur microsatellite lié au CMH afin de déterminer une méthode d’analyse à l’échelle populationnelle. Huit nouveaux allèles de CMH ont été détectés par séquençage haut débit. Le marqueur microsatellite présente un schéma d’amplification complexe et nécessite une optimisation des protocoles qui permettra de réduire les couts d’analyses de la variabilité du CMH à l’échelle populationnelle. Nos développements ouvrent de nouvelles perspectives pour l’étude de l’influence du CMH sur le choix de partenaire dans des populations sauvages de primates. / In many species, it has been shown that strategies of choice of socio-sexual partners by an individual are related to the phenotypic or genetic quality of these partners and are likely to maximize the quality of its descendants and improve its own fitness. We investigated the partner choice in western lowland gorilla females in studying their social dispersion and the relative influence of the social environment and the characteristics of adult males in females’ decisions, to stay in a social group or to emigrate, and in their choice of the group into which immigrate. We showed that females preferentially migrated towards breeding groups rather than solitary males and towards younger rather than aging groups. Groups of 10-15 individuals were avoided. Females emigrated from groups containing a large proportion of individuals affected by skin disease. In the short term after a demographic die-off due to an Ebola epidemic, female’s emigration rates declined in large groups, suggesting better reproductive and protective value of surviving males. The influence of the genetic characteristics of the sexual partners in the choice of females, in particular the genes of the major histocompatibility complex (MHC) genes that encode proteins involved in immune defenses, may be involved in partner choice in some primates. Its possible involvement had never been studied in the gorilla. In this perspective we have sought to develop a method to study this gene complex from non-invasive DNA samples (feces), that is to say with weakly concentrated and degraded DNA. We defined a new primer and then used high throughput sequencing, denaturing gradient gel electrophoresis, and a MHC-linked microsatellite marker to determine a population-level analysis method. Eight new MHC alleles were detected by high throughput sequencing. The microsatellite marker has a complex amplification pattern and requires protocol optimization that will reduce the cost of analyzing MHC variability at the population level. Our developments open new perspectives for the study of the influence of CMH on partner choice in wild populations of primates.

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