Le travail réalisé dans le cadre de cette thèse vise à l'approfondissement des connaissances sur l'impact de l'environnement gestationnel sur le développement de la commande respiratoire chez le nouveau-né. La respiration est une activité rythmique et autonome. La maturation des réseaux neuronaux impliqués dans son contrôle commence au cours de la gestation et persiste pendant la période postnatale. Le contrôle respiratoire est donc particulièrement susceptible à des variations de l'environnement intra-utérin. Nous avons étudié l'effet de deux stress gestationnels chroniques distincts : l'exposition à des cannabinoïdes et l'exposition à une hypoxie prénatale. A l'aide de techniques intégrées telles que la pléthysmographie à corps entier, éléctrophysiologiques comme la préparation de tronc cérébrale isolé ou les tranches de bulbes et immunohisto- et neurochimiques, nous avons pu caractériser l'impact des stress prénataux étudiés sur la plasticité respiratoire développementale. Nous avons pu établir un rôle central de l'anandamide dans la modulation de la commande respiratoire, probablement via des mécanismes noradrénergiques. L'exposition prénatale au WIN 55,212-2 induit une hyperventilation basale chez la souris nouveau-née qui semble relever d'altérations périphériques. Elle induit également une accentuation de la réponse centrale à l'hypoxie aigue et affecte l'apparition d'irrégularités respiratoires telles que les apnées. Quant à l'hypoxie prénatale, elle induit une hyperventilation basale d'origine centrale ainsi qu'une augmentation de l'activité catécholaminergique du tronc cérébrale. / Breathing is an autonomic rhythmic activity. The maturation of the neuronal networks responsible for breathing control begins in early gestation and persists throughout the neonatal period. This renders breathing control particularly susceptible to early insults arising from the intra uterine environment. We have studied the effects of two such gestational stress factors, namely prenatal exposure to cannabinoids and to gestational hypoxia. We use a wide array of in vivo and in vitro techniques in order to characterise the effect of the adverse intra uterine environment on the development of respiratory control. These include integrated techniques such as whole body plethysmography, electrophysiological preparations (en bloc and brainstem slice recordings) as well as immunohisto- and neurochemical approaches. We show that the prenatal stress factors induce developmental respiratory plasticity. This translates as heightened basal ventilation, observed following prenatal exposure to both cannabinoids and hypoxia. Comparisons between in vivo and in vitro techniques reveal a peripheral origin for the alterations observed following prenatal exposure to cannabinoids, suggesting a perturbation of the initiation and/or integration of information from the peripheral carotid bodies. Following prenatal hypoxia, respiratory perturbations have a central origin and can thus be observed in reduced preparations such as brainstem slice recordings. Neurochemical and immunohistochemical assays also reveal alterations in the bioaminergic modulation of the respiratory rhythm generator, perhaps underpinning the observed effects on respiratory control.

Rodent commensal species produce great damage in agriculture and urban areas. As invasive species they can endanger local species and are carriers and vectors of several important zoonoses. Control methods rely mainly on the use of warfarins, which can be inadvertently be taken up by untargeted species. Warfarins have also lost their efficacy in rodents due to the development of genetic resistance. In addition, these methods are considered inhumane as they cause a slow and painful death due to haemorrhages. Olfaction is a main source for environmental risk assessment by rodents, and it can be used to modify their use of space. My aim in this thesis was to identify behavioural reactions of the house mouse (Mus musculus), using laboratory strains as models of wild animals, to ecologically meaningful chemical messages, including predator and plant chemical olfactory cues. My results showed that mice avoided complex ferret olfactory cues and ethanol which is a ubiquitous chemical related to fruit rotting and ripening. The feline protein Fel d 1, which belongs to the secretoglobin family and is a major cat allergen in humans, did not elicit significant avoidance or alter foraging behaviour in mice. However, Trimethylthiazoline purified from fox faeces, elicited clear avoidance behaviour and stress responses. I carried out a bibliographic review to evaluate and discuss rodent pest control methods from an ethical standpoint. This literature showed that many of the current methods of pest control are considered inhumane, and do not tally with current society concerns and welfare standards in other domains such as farms or laboratory animals. These results raise new research questions to identify ferret and plant chemical compounds that can induce rodent avoidance, and to carry out next stage of research with wild animals both under laboratory and field conditions.

A socioecologia estuda a diversidade dos sistemas sociais a partir dos princípios da ecologia comportamental. Roedores são bons modelos para o estudo dos sistemas sociais por apresentarem elevada variação no comportamento social, a qual pode ser uma adaptação selecionada no passado evolutivo e/ou uma resposta adaptativa ao contexto ecológico atual. Estudar preás para investigar a flexibilidade da organização social é relevante porque, apesar de explorarem vários ambientes diferentes, esses animais podem apresentar certa rigidez comportamental. Nesse contexto, a hipótese que avaliamos é a de que a organização social dos preás Cavia magna, um herbívoro pouco estudado, encontrado do Norte do Uruguai ao Sul do Brasil, depende de determinantes ecológicos atuais, sendo uma resposta adaptativa. A hipótese alternativa é a de que a organização social é uma resposta adaptada, limitada por características selecionadas no passado. Para isso, (1) caracterizamos suas interações sociais; (2) avaliamos as distâncias interindividuais durante o forrageamento, (3) analisamos o padrão de agregação dos indivíduos e (4) comparamos seus comportamentos e organização social com os dados disponíveis de uma população da espécie ocorrente no Uruguai e com os dados de Cavia intermedia, uma espécie endêmica das Ilhas Moleques do Sul, em Santa Catarina que apresenta adaptações ao habitat insular. Os preás foram observados em uma área urbana costeira, dentro do campus do Instituto Federal de Santa Catarina (IFSC), em Florianópolis. Esse local apresenta isolamento da população em área pequena e com pouco risco de predação, isto é, uma área semelhante ao habitat insular. Observamos os preás na estação fria-seca e quente-úmida, por 60 dias. Concluímos que a população de C. magna do IFSC é social, pois encontramos grandes tamanhos médios de agregação, elevados Índices de Associação entre os indivíduos, e associações preferenciais em três grupos com conformação típica de harém. Constatamos que são poligínicos, porque o acesso às fêmeas diferiu entre os machos, e estes apresentaram mais comportamentos agonísticos que as fêmeas. A presença de hierarquia de dominância e ausência de comportamento territorialista dos machos indicaram que a poliginia foi sem defesa. Apesar de termos encontrado um sistema social semelhante ao de C. intermedia, não encontramos características típicas de síndrome insular. Dessa forma, corroboramos a hipótese de que a organização social dos preás é uma resposta adaptativa / Socioecology studies social systems applying the behavioral ecology principles. Studying rodents social systems represents a valuable opportunity once this group shows high variations on social behavior, which may be an adaptation selected in evolutionary past and/or an adaptative feedback to the ecological context. Investigate the social organization flexibility by studying cavies is relevant because of its relative behavioral rigidity, despite their occupation of different environments. In this context, we intend to evaluate our hypothesis on the Cavia magna, cavie social organization: it depends on current ecological factors, being an adaptive answer. C. magna is an herbivore found on northern Uruguay and south of Brazil. The alternative hypothesis is that the social organization is an adaptive answer, limited by reaction rules selected on the past. The cavies was observed in a coast urban area, inside of the Instituto Federal de Santa Catarina (IFSC), in continental Florianópolis, Brazil. The population is isolated in a small area with low predatory risk, being similar to an insulated habitat. We collected data on social interaction, interindividual distances during foraging, grouping pattern and sexual ratio. This data was compared to the available data of Cavia intermedia, from the Moleques do Sul archipelago, specie that was probably derived from C. magna and presents adaptations to the insular habitat. Cavies were observed for 60 days in cold-dry and hot-wet season. We have concluded that the studied C. magna population is social, given that we have found relatively large mean groups size, high Association Indexes between individuals, and preferred associations in three clusters with typical harem structure. We have also found that the population is polygynous, because the access to females differed between male individuals, and the males performed significantly more agonistic behaviors than females. The existence of a dominance hierarchy and the absence of male territorial behavior pointed to polygyny without defense. Even though the studied social system is similar to the one observed on C. intermedia, we did not encounter typical insular syndrome features on C. magna. Accordingly, we have supported the hypothesis that the cavies social organization is an adaptive answer

Studies in agricultural landscapes have shown that anthropogenic environments may be relevant to wildlife species. Given the extent of these areas efficient research methods are needed to assess its ecological value in terms of local diversity, such as the use of biological indicators. The main goal here was to evaluate the possible relationship between the native vegetation biomass and diversity of small mammals in a silvicultural landscape of São Paulo. The study was developed at Fazenda Três Lagoas, which is part of the \"Programa de Pesquisa em Biodiversidade\" (PPBio), at Angatuba municipality, State of São Paulo, and lasted nine months. From May 2015 to March 2016 nine sampling campaigns were carried over a grid of 15 pitfall traps, five in Eucalyptus plantations, five in native vegetation and five in abandoned pastures. In the Chapter 1 the distribution and abundance patterns of small mammals on a silvicultural landcape during the early second cycle of Eucalyptus plantation in Southeastern Brazil was evaluated. A total of 672 individuals from 15 species of the orders Rodentia (9 spp.) and Didelphimorphia (6 spp.) were captured and five new species were detected in the study area in comparison to the first cycle. Although these species are predominantly generalists, there were differences in the abundance of small mammals in the three environments. The presence of native vegetation patches associated with riparian areas and abandoned pastures and the role of small mammals as a food resource for predators on a trophic structure, gives a certain conservation value to silvicultural landscapes in southeastern Brazil. In the Chapter 2 the relationship between landscape metrics and patterns of diversity, distribution and abundance of small mammals in a silvicultural landscape were evaluated. The species richness and family diversity of small mammals have been predominantly determined by the percentage of native vegetation. However, the abundance of small mammals can be determined by an indirect estimate of the native vegetation biomass (i.e., NDVI), which can be considered a 3D landscape metric as it is related to volume. Therefore, to succeed in assessing the value of agricultural landscape, future studies should consider landscape context, as well as the landscape metrics associated with geospatial data analysis and the distinct responses of species. / Estudos em paisagens agrícolas têm mostrado que ambientes antrópicos podem ser relevantes para muitas espécies selvagens. Dada a extensão destas áreas, são necessários métodos eficientes de pesquisa para avaliar seu valor ecológico em termos de diversidade local, tais como o uso de indicadores biológicos. O presente estudo teve como objetivo geral avaliar a possível relação entre a biomassa de vegetação nativa e a diversidade de mamíferos de pequeno porte em uma paisagem silvicultural do estado de São Paulo. O estudo foi desenvolvido na Fazenda Três Lagoas, que é parte do Núcleo Angatuba do Programa de Pesquisa em Biodiversidade (PPBio), no município de Angatuba, Estado de São Paulo e teve a duração de nove meses. De maio de 2015 a março de 2016, foram realizadas campanhas mensais de amostragem em uma grade amostral com 15 conjuntos de armadilhas de interceptação e queda (pitfall), sendo cinco nas plantações de Eucalyptus spp., cinco em vegetação nativa e cinco em pasto abandonado. No Capítulo 1 foram avaliados os padrões de distribuição e abundância de pequenos mamíferos em uma paisagem silvicultural ao início do segundo ciclo de plantações de Eucalyptus no Sudeste do Brasil. Um total de 672 indivíduos de 15 espécies das ordens Rodentia (9 spp.) e Didelphimorphia (6 spp.) foram capturados e cinco novas espécies foram detectadas na área de estudo em relação ao primeiro ciclo. Embora as espécies presentes sejam predominantemente generalistas, houve diferença na abundância de pequenos mamíferos nos três ambientes. A presença de fragmentos de vegetação nativa associados a áreas ripícolas e pasto abandonado e o papel dos pequenos mamíferos como recurso alimentar para predadores em uma estrutura trófica, atribui um valor de conservação às paisagens silviculturais no sudeste do Brasil. No Capítulo 2, o objetivo foi avaliar a relação entre métricas da paisagem e padrões de diversidade, distribuição e abundância de pequenos mamíferos em uma paisagem silvícultural. A riqueza de espécies e a diversidade de famílias dos pequenos mamíferos tem sido predominantemente determinada pela área porcentual de vegetação nativa. No entanto, a abundância de pequenos mamíferos pode ser determinada por uma estimativa indireta da biomassa da vegetação nativa (e.g., NDVI), que pode ser considerada uma métrica de paisagem 3D, pois está relacionada ao volume. Portanto, para ter sucesso na avaliação do valor da paisagem agrícola, os estudos futuros devem considerar o contexto da paisagem, bem como as métricas da paisagem associadas à análise dos dados geoespaciais e as distintas respostas das espécies.

As relações filogenéticas em Rodentia são complexas, sendo a posição de Hystricognathi controversa quando analisada por dados morfológicos e moleculares. O presente estudo propõe uma reavaliação desta filogenia a partir de uma perspectiva comportamental. Seqüências probabilísticas do comportamento de autolimpeza (grooming) foram obtidas, através do programa EthoSeq, em um grupo de 12 espécies de roedores. O grupo interno é constituído por cinco Sciurognathi [Calomys callosus (Cc), Mesocricetus auratus (Ma), Rattus norvegicus (Rn), Mus musculus (Mm), e Meriones unguiculatus (Mu)] e sete Hystricognathi [Cavia aperea (Ca), C. porcellus (Cp), C. intermedia (Ci), Coendou prehensilis (Cop), Trinomys yonenagae (Ty), Thrichomys pachyurus (Tp) e Thrichomys laurentius (Tl), sendo esta espécie representada por duas populações coletadas na Bahia (BA) e no Piauí (PI), respectivamente). Duas espécies representaram os grupos externos: Felis silvestris f. catus e Oryctolagus cuniculus. A análise de sinal filogenético em seqüências de autolimpeza mostra que é necessário o uso de um conjunto de comportamentos organizados em diferentes graus de complexidade (unidades isoladas, díades, e seqüências mais longas) para a resolução das relações nos diferentes níveis taxonômicos estudados. Para a análise cladística usou-se o programa TNT e uma matriz composta por 23 caracteres contínuos (freqüência de autolimpeza) e 7.152 numéricos (seqüências de autolimpeza). A única árvore parcimoniosa obtida foi: (Fc, (Oc, (Cop, (Ci, (Ty, (((Ca, Cp), ((Tl-BA, (Tp, Tl-PI)), ((Mm, Rn), (Mu, (Cc, Ma)))))))))). A obtenção deste resultado mostra a adequação do uso de caracteres comportamentais no estudo de relações filogenéticas mesmo em grupos complexos 8 como Rodentia. Freqüência de autolimpeza é filogeneticamente informativo. Os resultados confirmam monofilia de Rodentia mas não resolvem a questão da monofilia de Hystricognathi. Indicam ainda que as duas populações de Thrichomys laurentius são distintas. Sugere-se que outros caracteres comportamentais em combinação com caracteres morfológicos e/ou moleculares devam ser incluídos em análises filogenéticas a fim de contribuir para esclarecimentos a respeito da evolução dos roedores, principalmente os histricognatas da América do Sul. / The phylogenetical relationships within Rodentia are complex, and the position of Hystricognathi differs when estimated through different kinds of data (morphology or DNA). This paper focuses on a still different kind of data: we estimate the phylogeny of the group through behavioral characters. We obtained probabilistic grooming sequences with the program EthoSeq, in a group of 12 rodent species. The ingroup consisted of five Sciurognathi [Calomys callosus (Cc), Mesocricetus auratus (Ma), Rattus norvegicus (Rn), Mus musculus (Mm), e Meriones unguiculatus (Mu)] and seven Hystricognathi [Cavia aperea (Ca), C. porcellus (Cp), C. intermedia (Ci), Coendou prehensilis (Cop), Trinomys yonenagae (Ty), Thrichomys pachyurus (Tp) e Thrichomys laurentius (Tl), this last species represented by two different populations, one from Bahia and another from Piauí state. The outgroup consisted of two species: Felis silvestris f. catus and Oryctolagus cuniculus. The analysis shows that the use of different levels of behavioral complexity (isolated behavioral units, sequences of two units dyads, and longer sequences routines) is necessary for the resolution of the relationships of the taxa studied. The program TNT was used for the cladistic analysis of a matrix with 23 continuous characters (frequency of grooming units) and 7152 discrete characters (grooming sequences). We obtained one single most parsimonious tree: (Fc, (Oc, (Cop, (Ci, (Ty, (((Ca, Cp), ((Tl-BA, (Tp, Tl-PI)), ((Mm, Rn), (Mu, (Cc, Ma)))))))))). This result shows that behavioral characters are adequate to solve the internal relationships even of complex groups such as Rodentia. There is phylogenetic signal in frequency of grooming units. Although Rodents result monophyletic in our analysis, we could not solve the relationships within Hystricognathi. The two populations of Thrichomys laurentius appear as 10 distinct species. We suggest that other behavioral characters should be combined with other, morphological and/or molecular databases, in order to clarify the relationships within Rodentia, specially within the South America histricognaths.

Analisou-se por métodos quantitativos e qualitativos o testículo de roedores histricomorfos nas fases, pré-púbere, púbere e adulto da Paca (Cuniculus paca), Cutia (Dasyprocta leporina) e Porquinho-da-índia (Cavia porcellus). Mediante as técnicas de microscopia de luz, microscopia eletrônica de varredura, microscopia eletrônica de transmissão e método estereológico. Verificou-se a influência do Letrozol um inibidor da enzima aromatase nas dosagens de 0,15mg\\kg e 1,0 mg\\kg, sobre a morfologia testicular de pacas macho. Este modelo animal apresenta importância, comercial e científica sendo excelente alternativa para a pesquisa, colaborando com o desenvolvimento de investigações vitais ao homem e aos próprios animais. Os resultados desta investigação demonstraram, que os aspectos qualitativos da morfologia testicular do Porquinho-da-índia, Cutia e de Paca foram semelhante nas fases pré-púbere, púbere e adulta. As avaliações quantitativas do Porquinho-da-índia e Cutia realizados mediante o método estereológico permitiram quantificar parâmetros, sem hipóteses de forma, tamanho, orientação ou distribuição das partículas contadas, demonstrando ser um método imparcial e confiável para ser aplicado em estudos de reprodução. Considerando o estrógeno ser essencial para a função da espermatogênese, o efeito do Letrozol no testículo da paca (Cuniculus paca), sugeriu que a inibição da enzima aromatase mediante a utilização de Letrozol na dosagem de 0,15mg \\kg, sugeriu em um aumento no número das células de Sertoli, refletindo sobre as demais células testiculares, comparando com o testículo basal (controle). O testículo tratado (Letrozol) demonstrou epitélio germinativo íntegro, sendo este dado importante para a reprodução. No animal púbere houve um aumento no número de células de- Sertoli, semelhante ao descrito anteriormente. O epitélio seminífero mostrou com alterações morfológicas, tais como proliferação celular, presença de células germinativas com características apoptóticas, e vacúolos e núcleos em picnose. Estes dados poderão ser úteis para o estudo da Síndrome da Disgenesia testicular / Analysis by quantitative and qualitative methods testicular histricomorfs rodents in phases, pre-pubertal, pubertal and adult paca (Cuniculus paca), agouti (Dasyprocta leporina) and guinea-pig (Cavia porcellus). By means of light microscopy techniques, scanning electron microscopy, transmission electron microscopy, stereological method and the influence of an aromatase inhibitor, the Letrozole in dosages of 0.15 mg\\kg and 1.0 mg\\kg on testicular male morphology paca. This animal model has importance, excellent commercial and scientific alternative to research, contributing to the development of vital research to humans and from animals themselves. The results of this research have shown that the qualitative aspects of testicular morphology guinea-pig, Agouti and paca were similar in pre-pubertal, pubertal and adult stages. Quantitative assessments of the guinea-pig and agouti performed by the stereological method allowed quantify parameters, no change of shape, size, orientation or distribution of particles counted, it is proving to be a partial and reliable method to be applied to reproduction studies. Considering the estrogen is essential for the function of spermatogenesis, the effect of Letrozole in the testis of paca (Cuniculus paca), suggested that inhibition of aromatase enzyme through the use of Letrozole in a dosage of 0.15 mg\\kg suggested in an increase in number of Sertoli cells, reflecting on the other testicular cells, comparing the baseline testis (control). The treaty testis (Letrozole) showed intact germinal epithelium, which is important data for reproduction. In pubertal animals there was an increase in the number of de Sertoli cells, similar to that described above. The seminiferous epithelium showed to morphological changes such as cell proliferation, the presence of germ cells with apoptotic features and vacuoles and nuclei picnosis. These data may be useful for the study of testicular dysgenesis syndrome

Com o objetivo de identificar Toxoplasma gondii e Neospora caninum em roedores urbanos da Grande São Paulo (SP) 217 roedores (quatro camundongos -Mus musculus, 20 ratazanas - Rattus norvegicus e 193 ratos de telhado - Rattus rattus) foram capturados entre abril de 2005 e fevereiro de 2008, para realização do diagnóstico biológico e molecular. Das 20 ratazanas (Rattus norvegicus) capturadas apenas uma foi positiva para T. gondii pelo bioensaio, correspondendo a 5% de positividade entre as ratazanas e 0,46% entre todos os roedores capturados. O isolado obtido dessa ratazana foi caracterizado como genótipo recombinante I, III e u-1 por PCR-RFLP, similar ao isolado previamente descrito e obtido de duas ovelhas e um gato, todos do Estado de São Paulo. Quatro amostras de roedores negativos ao bioensaio resultaram como positivas ao T. gondii pela nested PCR B1. Entretanto, quando submetidas à nested PCR ITS1 e à restrição enzimática (RFLP) não houve confirmação desse resultado em três delas. Em relação ao N. caninum, amostras de tecido cerebral e cardíaco de 121 roedores foram examinadas por nested PCR Nc5, tendo sido encontradas 12 amostras positivas, provenientes de 10 roedores. Quando submetidas à nested PCR ITS1 e à restrição enzimática (RFLP) N. caninum não foi confirmado em nenhuma das amostras. Este estudo conclui que a ocorrência de T. gondii e N. caninum em roedores urbanos da Grande São Paulo (SP) é baixa, sugerindo que estes animais não possuem papel importante na cadeia epidemiológica como reservatórios desses agentes para predadores como os cães e gatos urbanos. / In order to identify Toxoplasma gondii and Neospora caninum in urban rodents from the Great São Paulo (SP) 217 rodents (four Mus musculus, 20 Rattus norvegicus and 193 Rattus rattus) were captured between April 2005 and February 2008 to biological and molecular diagnosis. One out of the 20 Rattus norvegicus was considered positive by bioassay in mice, corresponding to a 5% positivity among Rattus norvegicus and a 0.46% positivity considering all captured rodents. The isolate from this rat was characterized as a recombinant I, III and u-1 genotype by RFLP-PCR. This characterization had been previously described from isolates obtained from two sheep and one cat also from São Paulo state. Four samples from rodents with negative results by bioassay were positive to T. gondii by nested PCR B1. However, when tested with nested PCR ITS1 and RFLP these results were not confirmed in three of these samples. Regarding N. caninum, brain and heart samples of 121 rodents were examined by nested PCR Nc5 and 12 samples from 10 rodents were positive. When tested with nested PCR ITS1 and RFLP all of these samples turned out to be negative. This study concludes that T. gondii and N. caninum have low occurrence in urban rodents in the Great São Paulo area, and they are not important as T. gondii and/or N. caninum reservoirs to predators like urban cats and dogs.

Cette thèse porte sur l'anatomie et la morphologie du complexe crânien chez les murinés. Ses objectifs sont de démontrer et de décrire le lien morpho-fonctionnel entre le crâne et la force de morsure, représentant la performance, d'identifier les sources génétiques de la variation de la performance et de la morphologie, et de comprendre comment la variation morpho-fonctionnelle dépend du mode de vie d'une espèce.La première partie décrit l'anatomie de l'appareil masticateur dans le genre Mus. Des différences fonctionnelles et liées au régime alimentaire sont montrées. Puis, on s'intéresse au lien entre morphologie et fonction, et aux proxies morpho-anatomiques permettant d'estimer la force de morsure. Un modèle biomécanique des muscles masticateurs est d'abord utilisé. Les estimations obtenues sontproches des mesures in vivo au niveau interspécifique, mais moins précises au niveau intraspécifique.L'avantage mécanique et la forme de la mandibule sont ensuite utilisés comme proxies. La force de morsure estimée et réelle sont corrélées au niveau interspécifique, mais moins au niveau intraspécifique, avec des différences selon les espèces. Pour expliquer ces imprécisions, la variation ontogénétique de la force de morsure et de la forme de la mandibule sont décrites. Lorsque l'âge est contrôlé, le développement osseux ralentit plus tôt que celui de la force de morsure, ce qui peut expliquer les biais trouvés dans les estimations de la force de morsure.La deuxième partie se concentre sur les sources génétiques des variations morpho-fonctionnelles. Chez Mus minutoides, des changements sur les chromosomes sexuels produisent des différences de taille et de force de morsure. Les mâles féminisés de cette espèces sont plus agressifs que les autres individus, et montrent une force de morsure plus puissante, principalement grâce à unplus gros crâne. Le(s) gène(s) féminisant produis(ent) donc des changements à l'échelle de l'organisme tout entier. La section suivante s'intéresse aux liens entre consanguinité, asymétrie et performance chez la souris domestique. Les souris les plus consanguines ne montrent pas d'augmentation de l'asymétrie de leurs mandibules, et la performance des souris les plus consanguines ou les plus asymétriques n'est pas affectée. Enfin, l'héritabilité de la force de morsure et de la morphologie est estimée. La force de morsure in vivo n'est pas héritable, bien que la morphologie le soit. Etant donné le lien entre morpho-anatomie et force de morsure, ces résultats suggèrent que les changements morphologiques sont des voies de moindre résistance évolutive, et qu'ils peuvent être à l'origine de changements de performance.La dernière partie utilise la morphologie et la performance en tant que caractères liés à l'écologie des espèces. La première section s'intéresse aux différences de performance entre Apodemus sylvaticus et Mus spretus, qui partagent leur habitat et leurs ressources alimentaires, malgré une différence de taille marquée. Nos résultats montrent un recouvrement des distributions des forces de morsures, soutenant l'hypothèse d'un régime alimentaire commun. Cette coexistence pourrait être due à une abondance de ressources là où ces espèces sont syntopiques. Enfin, la variation morphologique est quantifiée chez plusieurs murinés d'Asie du Sud-Est. Les espèces de rats commensaux et généralistes sont moins variables que les autres espèces. Les espèces synanthropiques montrent des réponses morpho-fonctionnelles convergentes entre localités qui suggèrent qu'elles partagent des patrons communs de réponse et donc qu’elles peuvent s'adapter aux variations environnementales régionales induites par l’homme. L'approche utilisée dans cette thèse nous a permis de montrer le lien entre variation génétique,phénotypique et écologique. Ce lien parfois difficile à décrire, est cependant à la base de l'apparition de nouvelles formes et espèces, et constitue un aspect crucial de la biologie de l'évolution. / The theme of this thesis is the anatomy and morphology of the cranio-mandibular complexin various species of murine rodents. The main objectives are to describe the morpho-functional link between the skull and bite force as a measure of performance, to identify the genetic sources of morphological and performance variation, and finally to understand how morpho-functional variation depends on a species diet and lifestyle. The first part describes the anatomy of the masticatory apparatus in the genus Mus. Differences were found, which could be interpreted functionally and linked to variation in diets. The first part also investigates the links between morpho-anatomy and function, and various morphological proxies used for estimating bite force. This is done by building a biomechanical model of masticatory muscles. The bite force estimates obtained match the in vivo measurements at the inter-specific level, but are less precise at the intra-specific level. Then, two osseous mandibular proxies of bite force are compared (lever arms and their mechanical advantage, and its shape data). In vivo and estimated bite force werewell related at the inter-specific level, but less at the intra-specific level, depending on the species. To explain these imprecisions, the ontogenetic variation of bite force and mandibular morphology isdescribed. Under controlled age, the bony development is slowing down earlier than bite force, whichcan partly explain the inconsistencies of estimated bite force.The second part focuses on the genetics of morphological and functional variation. In Musminutoides, changes in the sexual chromosomes entail size and performance changes. The feminized males found in this species are known to be more aggressive than other individuals, and they produce ahigher bite force, mainly due to an increase in skull size. The feminizing gene(s) therefore drive whole-organism-scale changes. Then, the links between inbreeding, asymmetry and performance areinvestigated in the house mouse. The most inbred mice do not experience an increase in the asymmetry of their mandibles. Contrary to expectations, the performance of the most inbred or most asymmetric mice do not decrease and differences in asymmetry levels have no influence on biting performance.The last section estimates the heritabilities of bite force and morphology. In vivo bite force is notheritable, but some morphological characters are. Given the functional link between morpho-anatomyand bite force shown in the first part, these results suggest that morphological changes represente volutionary pathways of least resistance, and drive changes in performance rather than behavioral or related traits.The last part took morphology and performance as linked to a species' niche. The first sectionexplores the differences between Apodemus sylvaticus and Mus spretus. Both share their habitat and food resources, in spite of a marked size difference. Results show great overlap between their bite force distributions supporting the hypothesis of a shared diet. The absence of shift in a trait related toresource use may be due to a large abundance of the food resources where both species are found insyntopy. In the final section the morphological variation in several rodents from Southeast Asia wasquantified. Less morphological variability is found in generalist and commensal rats by comparison toother species. At the community level, synanthropic species show frequent convergent responsesbetween localities in terms of bite force and morphology. These common patterns in response suggestthat synanthropic species tend to be very adaptable to regional environmental differences.The approaches used in this thesis enable us to show the link between genetic, phenotypic andecological variation. This link, sometimes difficult to describe, is nevertheless at the root of theappearance of new forms and species, and constitutes a crucial aspect of evolutionary biology.

Male C7BL/6J mice were implanted with bilateral dorsal CA1 guide cannulae. After confirming that intrahippocampal microinfusion of muscimol impaired hippocampal function, demonstrated by impaired performance in the Morris water maze, the influence of intrahippocampal muscimol was tested in the Novel Object Recognition paradigm. During a test session 24 h after the last habituation/sample session, mice were presented with one familiar object and one novel object. Successful retention of object memory was inferred if mice spent more time exploring the novel object than the familiar object. Results demonstrate that muscimol infused into dorsal CA1 region prior to the test session eliminates novel object preference, indicating that the hippocampus is necessary for the retrieval of this non-spatial memory - a topic that has garnered much debate. Understanding the similarities between rodent and human hippocampal function could enable future animal studies to effectively answer questions about diseases and disorders affecting human learning and memory. / by Lisa Rios. / Thesis (M.A.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.

Objetivou-se neste estudo descrever a anatomia macroscópica dos pulmões e da árvore brônquica da paca, além de padronizar a vascularização arterial pulmonar, mediante dissecação da árvore brônquica e do tronco pulmonar injetado com neoprene látex corado, de dez pulmões devidamente fixados em solução aquosa de formol à 10%, de pacas adultas, machos e fêmeas, que vieram a óbito, por motivos diversos os quais não afetaram os órgãos em questão e eram provenientes do criadouro de pacas do Setor de Animais Silvestres da do Departamento de Zootecnia da Faculdade de Ciências Agrárias e Veterinárias - Câmpus de Jaboticabal, da Universidade Estadual Paulista - UNESP. Foi observado em 100% dos casos estudados que o pulmão direito da paca está constituído por quatro lobos bem delimitados por fissuras interlobares: cranial; médio, este bilobado em parte cranial e parte caudal; lobo acessório; o pulmão esquerdo possui três lobos bem delimitados: cranial, este bilobado em parte cranial e parte caudal; caudal e um pequeno lobo acessório. O lobo caudal, mais desenvolvido, tem em sua face medial a justaposição do lobo acessório. Também em todos os casos observados, apenas um padrão de distribuição brônquica foi observado.Quanto à vascularização, a artéria pulmonar direita, emite dois ramos distintos para o lobo cranial, além dos ramos independentes para a parte cranial e parte caudal do lobo médio, o ramo do lobo acessório e o ramo do lobo caudal; a artéria pulmonar esquerda emite dois ramos ascendentes e um descendente, respectivamente para as porções cranial e caudal do lobo cranial; o ramo do lobo caudal é irrigado pela própria continuação da artéria pulmonar esquerda que emite de cinco a seis ramos dorsais e de sete a oito ramos ventrais. / The purpose of this study was to describe the anatomy of the lungs and the distribution of the branches of the pulmonary arteries of the pacas by dissection of the bronchial tree and of the lung trunk injected with coloured latex neoprene of ten lungs properly fastened in aqueous solution of formol to the 10%, of adult pacas, males and female. It was observed in 100% of the cases studied that the right lung of the paca is constituted by four lobes, which were de1imnited by well defined inter1obar grooves. Four 1obes were indentified: crania1, medium, caudal and accessory, the 1ast one subdivided into lateral and media1 portions. The 1eft 1ung had on1y two lobes: crania1 and cauda1. The right pu1monary artery sent out the branch of the cranial lobe, which divided itself into ascending and descending branches. The next branch arising from the right pulmonary artery was the branch of the accessory 1obe and divided itself into lateral and media1 branches. The 1ast branch arising form the pu1monary artery was the branch of the cauda1 1obe, which originated seven to 16 arterial branches. The left pulmonary artery sent out the independent ascending and descending branches and in the end continued as the branch of the caudal lobe, which sent out six to 14 arterial branches.