637 resultados para Rusa Deer


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v. 17, n. 2, p. 296-302, abr./jun. 2016.

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L’utilisation de l’espace par une proie herbivore est souvent modulée par le compromis entre l’acquisition de fourrage et l’évitement de la prédation. Nous avons testé l’effet de la manipulation de la disponibilité de fourrage et du ratio couvert forestier/ouverture sur l’utilisation de l’espace par le cerf de Virginie (Odocoileus virginianus) et sa vulnérabilité à la chasse sportive sur l’île d’Anticosti. Nos résultats ont démontré que l’utilisation de l’espace par le cerf et sa vulnérabilité à la chasse peuvent être modifiées par différentes composantes structurales de l’habitat. L’augmentation de la disponibilité de fourrage a entrainé une plus grande utilisation des prairies fertilisées par le cerf, tandis que la diminution du ratio couvert forestier/ouverture a augmenté sa vulnérabilité à la chasse. Ces résultats procurent des pistes de solutions pour les gestionnaires fauniques qui doivent à la fois réduire les dommages causés par les hautes densités de cerfs et satisfaire les chasseurs en maintenant un nombre élevé d’observation de cerfs.

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Vector-borne disease emergence in recent decades has been associated with different environmental drivers including changes in habitat, hosts and climate. Lyme borreliosis is among the most important vector-borne diseases in the Northern hemisphere and is an emerging disease in Scotland. Transmitted by Ixodid tick vectors between large numbers of wild vertebrate host species, Lyme borreliosis is caused by bacteria from the Borrelia burgdorferi sensu lato species group. Ecological studies can inform how environmental factors such as host abundance and community composition, habitat and landscape heterogeneity contribute to spatial and temporal variation in risk from B. burgdorferi s.l. In this thesis a range of approaches were used to investigate the effects of vertebrate host communities and individual host species as drivers of B. burgdorferi s.l. dynamics and its tick vector Ixodes ricinus. Host species differ in reservoir competence for B. burgdorferi s.l. and as hosts for ticks. Deer are incompetent transmission hosts for B. burgdorferi s.l. but are significant hosts of all life-stages of I. ricinus. Rodents and birds are important transmission hosts of B. burgdorferi s.l. and common hosts of immature life-stages of I. ricinus. In this thesis, surveys of woodland sites revealed variable effects of deer density on B. burgdorferi prevalence, from no effect (Chapter 2) to a possible ‘dilution’ effect resulting in lower prevalence at higher deer densities (Chapter 3). An invasive species in Scotland, the grey squirrel (Sciurus carolinensis), was found to host diverse genotypes of B. burgdorferi s.l. and may act as a spill-over host for strains maintained by native host species (Chapter 4). Habitat fragmentation may alter the dynamics of B. burgdorferi s.l. via effects on the host community and host movements. In this thesis, there was lack of persistence of the rodent associated genospecies of B. burgdorferi s.l. within a naturally fragmented landscape (Chapter 3). Rodent host biology, particularly population cycles and dispersal ability are likely to affect pathogen persistence and recolonization in fragmented habitats. Heterogeneity in disease dynamics can occur spatially and temporally due to differences in the host community, habitat and climatic factors. Higher numbers of I. ricinus nymphs, and a higher probability of detecting a nymph infected with B. burgdorferi s.l., were found in areas with warmer climates estimated by growing degree days (Chapter 2). The ground vegetation type associated with the highest number of I. ricinus nymphs varied between studies in this thesis (Chapter 2 & 3) and does not appear to be a reliable predictor across large areas. B. burgdorferi s.l. prevalence and genospecies composition was highly variable for the same sites sampled in subsequent years (Chapter 2). This suggests that dynamic variables such as reservoir host densities and deer should be measured as well as more static habitat and climatic factors to understand the drivers of B. burgdorferi s.l. infection in ticks. Heterogeneity in parasite loads amongst hosts is a common finding which has implications for disease ecology and management. Using a 17-year data set for tick infestations in a wild bird community in Scotland, different effects of age and sex on tick burdens were found among four species of passerine bird (Chapter 5). There were also different rates of decline in tick burdens among bird species in response to a long term decrease in questing tick pressure over the study. Species specific patterns may be driven by differences in behaviour and immunity and highlight the importance of comparative approaches. Combining whole genome sequencing (WGS) and population genetics approaches offers a novel approach to identify ecological drivers of pathogen populations. An initial analysis of WGS from B. burgdorferi s.s. isolates sampled 16 years apart suggests that there is a signal of measurable evolution (Chapter 6). This suggests demographic analyses may be applied to understand ecological and evolutionary processes of these bacteria. This work shows how host communities, habitat and climatic factors can affect the local transmission dynamics of B. burgdorferi s.l. and the potential risk of infection to humans. Spatial and temporal heterogeneity in pathogen dynamics poses challenges for the prediction of risk. New tools such as WGS of the pathogen (Chapter 6) and blood meal analysis techniques will add power to future studies on the ecology and evolution of B. burgdorferi s.l.

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Indospicine (L-2-amino-6-amidinohexanoic acid) is a natural hepatotoxin found in all parts of some Indigofera plants such as I. linnaei and I. spicata. Several studies have documented a susceptibility to this hepatotoxin in different species of animals, including cattle, sheep, dogs and rats, which are associated with mild to severe liver disease after prolonged ingestion. However, there is little published data on the effects of this hepatotoxin in camels, even though Indigofera plants are known to be palatable to camels in central Australia. The secondary poisoning of dogs after prolonged dietary exposure to residual indospicine in camel muscle has raised additional food safety concerns. In this study, a feeding experiment was conducted to investigate the in vivo accumulation, excretion, distribution and histopathological effects of dietary indospicine on camels. Six young camels (2 – 4 year old), weighing 270 − 390 kg were fed daily a roughage diet consisting of Rhodes grass hay and lucerne chaff, supplemented with Indigofera and steam flaked barley. Indigofera (I. spicata) was offered at 597 mg DM/kg body weight (bw)/day designed to deliver 337 µg indospicine/kg bw/day, and fed for a period of 32 days. Blood and muscle biopsies were collected over the period of the study. Concentrations of indospicine in the plasma and muscle biopsy samples were quantitated by validated ultra-performance liquid chromatography−tandem mass spectrometry (UPLC−MS/MS). The highest concentrations in plasma (1.01 mg/L) and muscle (2.63 mg/kg fresh weight (fw)) were found at necropsy (day 33). Other tissues were also collected at necropsy and analysis showed ubiquitous distribution of indospicine, with the highest indospicine accumulation detected in the pancreas (4.86 ± 0.56 mg/kg fw) and liver (3.60 ± 1.34 mg/kg fw); followed by the muscle, heart and kidney. Histopathological examination of liver tissue showed multiple small foci of predominantly mononuclear inflammatory cells. After cessation of Indigofera intake, indospicine present in plasma in the remaining 3 camels had a longer terminal elimination half-life (18.6 days) than muscle (15.9 days), and both demonstrated mono-exponential decreases.

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A pressing challenge for the study of animal ethics in early modern literature is the very breadth of the category “animal,” which occludes the distinct ecological and economic roles of different species. Understanding the significance of deer to a hunter as distinct from the meaning of swine for a London pork vendor requires a historical investigation into humans’ ecological and cultural relationships with individual animals. For the constituents of England’s agricultural networks – shepherds, butchers, fishwives, eaters at tables high and low – animals matter differently. While recent scholarship on food and animal ethics often emphasizes ecological reciprocation, I insist that this mutualism is always out of balance, both across and within species lines. Focusing on drama by William Shakespeare, Ben Jonson, and the anonymous authors of late medieval biblical plays, my research investigates how sixteenth-century theaters use food animals to mediate and negotiate the complexities of a changing meat economy. On the English stage, playwrights use food animals to impress the ethico-political implications of land enclosure, forest emparkment, the search for new fisheries, and air and water pollution from urban slaughterhouses and markets. Concurrent developments in animal husbandry and theatrical production in the period thus led to new ideas about emplacement, embodiment, and the ethics of interspecies interdependence.

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The analysis of a faunal collection from a storage silo found in the castle of Aljezur, dating from the Almohad period (XII/XIIIth centuries AD), is presented. It appears that the community occupying the castle concentrated on hunting species such as the rabbit, wild boar, red deer and Iberian lynx, while evidences of stockbreeding were scarce and centered upon caprines with horses and chicken playing minor role. The presence of a large dog has been assumed to be an aid for hunting but possibly also in herd keeping. With the exception of the lynx, all large mammals evidenced traces of consumption. The domestic cat is taken to represent a pet whereas the lynx had probably a role as a fur provider. It should be noted that equids and the pond turtle were probably food items. Rodents are taken to represent commensals whereas the toad of the Genus Bufo probably represented an intrusive element.

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O Serviço de Referência (SR), incorporando na sua organização, funcionamento e comunicação com o utilizador um conjunto de potencialidades proporcionadas pela tecnologia, assume um papel fundamental na luta contra a desigualdade e o analfabetismo digital, no fomento da literacia da informação e na criação de conhecimento. A percepção do valor e das fragilidades do SR nas bibliotecas públicas em Portugal levanta a questão sobre como contribuir para o seu desenvolvimento. A presente investigação, visando a construção de alicerces numa perspectiva de evolução, parte da análise de documentos orientadores internacionais da RUSA/ALA (Reference and User Services Association / American Library Association) e da IFLA (International Federation of Library Association) e da observação de características estruturais da Rede Nacional de Biblioteca Públicas (RNBP), para a concepção de soluções de desenvolvimento do SR a aplicar a esta realidade concreta. Seguindo um paradigma compreensivo indutivo, com uma orientação baseada na Grounded Theory, esta pesquisa privilegia o contexto da descoberta e a construção de uma teoria. No plano empírico cumpre uma complementaridade de técnicas qualitativas e quantitativas, com recurso a uma triangulação metodológica. O campo de análise abrange a totalidade das bibliotecas públicas portuguesas integradas na RNBP em Portugal. Visando aspectos funcionais e materiais, são analisados dados preexistentes e aplicadas técnicas de observação directa e inquérito por questionário. Visando aspectos sociais, são efectuadas seis entrevistas semi-estruturadas. Os resultados apontam para uma situação de estagnação das bibliotecas da RNBP e para um funcionamento não estruturado e informal do SR, na maioria dos casos em que se verifica a sua disponibilização. Fundamentada a necessidade de evolução, e do investimento que nele possa ser feito, é construído um modelo, seguindo uma estratégia por níveis, flexíveis e adaptáveis às necessidades e aos recursos de cada biblioteca, que visa o desenvolvimento incremental e congruente daquele serviço; Abstract: The Reference Service in public libraries in Portugal. Development model from international guidelines. Incorporating in its organization, procedures and communication with the users a set of tools brought by technology, Reference Service (RS) plays a key role in the struggle against inequality and digital illiteracy, promoting information literacy and creating knowledge. The perception of the value of RS and the weaknesses in public libraries in Portugal raise the question on how to contribute to its development. In order to build RS foundations on an evolutionary perspective, this research analyzes RUSA / ALA (Reference and User Services Association / American Library Association) and IFLA (International Federation of Library Association) international guidelines and the structural characteristics of the Portuguese National Public Library Network (RNBP), with the objective of creating a solution for the development of that service to be applied to this reality. Following an inductive comprehensive paradigm, with an orientation based on Grounded Theory, this research focuses on the context of discovery and the construction of a theory. Empirically it fulfils complementary qualitative and quantitative techniques, using a methodological triangulation. The field of analysis covers Portuguese public libraries integrating the RNBP. Aiming at functional and material aspects, direct observation techniques and a survey by questionnaire are applied. Targeting social aspects, six semistructured interviews are carried out. The results point to a situation of stagnation in the RNBP as well as the unstructured and informal performance of the SR, which justifies the need for evolution and investment. A model is constructed, following a strategy based on levels, flexible and adaptable to the needs and resources of each library, with the perspective of an incremental and consistent development of this service.

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Environmental indicators have been proposed as a means to assess ecological integrity, monitoring both chemical and biological stressors. In this study, we used nestling bald eagles as indicators to quantify direct or indirect tertiary-level contaminant exposure. The spatial and temporal trends of polychlorinated biphenyl (PCB) congeners were evaluated in nestling plasma from 1999–2014. Two hexa-chlorinated congeners, PCB-138 and 153, were detected with the highest frequency and greatest concentrations throughout Michigan. Less-chlorinated congeners such as PCB-52 and 66 however, comprised a greater percentage of total PCB concentrations in nestlings proximate to urbanized areas, such as along the shorelines of Lake Erie. Toxic equivalents were greatest in the samples collected from nestlings located on Lake Erie, followed by the other Great Lakes spatial regions. Nestling plasma samples were also used to measure concentrations of the most heavily-used group of flame retardants, brominated diphenyl ethers (BDEs), and three groups of alternative flame retardants, non-BDE Brominated Flame Retardants (NBFRS), Dechloranes, and organophosphate esters (OPs). BDE-47, 99 and 100 contributed the greatest to total BDE concentrations. Concentrations of structurally similar NBFRs found in this study and recent atmospheric studies indicate that they are largely used as replacements to previously used BDE mixtures. A variety of Dechloranes, or derivatives of Mirex and Dechlorane Plus, were measured. Although, measured at lesser concentrations, environmental behavior of these compounds may be similar to mirex and warrant future research in aquatic species. Concentrations of OPs in nestling plasma were two to three orders of magnitude greater than all other groups of flame retardants. In addition to chemical indicators, bald eagles have also been proposed as indicators to identify ecological stressors using population measures that are tied to the fitness of individuals and populations. Using mortality as a population vitality rate, vehicle collisions were found to be the main source of mortality with a greater incidence for females during white-tailed deer (Odocoileus virginianus) hunting months and spring snow-melt. Lead poisoning was the second greatest source of mortality, with sources likely due to unretrieved hunter-killed, white-tailed deer carcasses, and possibly exacerbated by density-dependent effects due to the growing population in Michigan.

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El constructivismo ruso se define como una práctica artística que respondió a las demandas sociales y culturales de una nueva sociedad. Se desarrolló como movimiento vanguardista que se propuso realizar un programa de vinculación de la obra artística con la vida, dejando atrás las formas del arte burgués y abriendo nuevas posibilidades a las funciones del arte en las condiciones sociales de la Revolución. El presente trabajo se propone la actualización de ese legado, me-diante apropiaciones irónicas de algunos de sus productos, en relación con las representaciones del heroísmo y el triunfalismo, del héroe y las masas, en los procesos políticos y culturales de la actualidad. En la medida que ese género de lenguaje ha sido utilizado en otros contex-tos, y las formulas constructivistas desbordan su enclave original en otras coor-denadas geopolíticas, este proyecto procura aprovechar las formulaciones ideoestéticas que fueron sustento de las propuestas constructivistas y productivis-tas al respecto de las experimentaciones del fotomontaje, la faktura y la factogra-fia.

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A espécie é uma das mais comuns no Pantanal, mas nem por isso dispensa estudos e atenção dos cientistas. Sua presença como podador ajuda a moldar a paisagem.

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Búsqueda del equilibrio político-económico Ruso: contexto político y económico de Rusia desde 1991 – Política exterior energética durante los mandatos presidenciales de Dmitri Medvédev y Vladimir Putin (2008-2015) – Instrumentalización del poder energético en la política exterior Rusa

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Posttraumatic stress and PTSD are becoming familiar terms to refer to what we often call the invisible wounds of war, yet these are recent additions to a popular discourse in which images of and ideas about combat-affected veterans have long circulated. A legacy of ideas about combat veterans and war trauma thus intersects with more recent clinical information about PTSD to become part of a discourse of visual media that has defined and continues to redefine veteran for popular audiences. In this dissertation I examine realist combat veteran representations in selected films and other visual media from three periods: during and after World Wars I and II (James Allen from I Am a Fugitive from a Chain Gang, Fred Derry and Al Stephenson from The Best Years of Our Lives); after the Vietnam War (Michael from The Deer Hunter, Eriksson from Casualties of War), and post 9/11 (Will James from The Hurt Locker, a collection of veterans from Wartorn: 1861-2010.) Employing a theoretical framework informed by visual media studies, Barthes’ concept of myth, and Foucault’s concept ofdiscursive unity, I analyze how these veteran representations are endowed with PTSD symptom-like behaviors and responses that seem reasonable and natural within the narrative arc. I contend that veteran myths appear through each veteran representation as the narrative develops and resolves. I argue that these veteran myths are many and varied but that they crystallize in a dominant veteran discourse, a discursive unity that I term veteranness. I further argue that veteranness entangles discrete categories such as veteran, combat veteran, and PTSD with veteran myths, often tying dominant discourse about combat-related PTSD to outdated or outmoded notions that significantly affect our attitudes about and treatment of veterans. A basic premise of my research is that unless and until we learn about the lasting effects of the trauma inherent to combat, we hinder our ability to fulfill our responsibilities to war veterans. A society that limits its understanding of posttraumatic stress, PTSD and post-war experiences of actual veterans affected by war trauma to veteranness or veteran myths risks normalizing or naturalizing an unexamined set of sociocultural expectations of all veterans, rendering them voice-less, invisible, and, ultimately disposable.

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The presence of methicillin-susceptible Staphylococcus aureus (MSSA) was analyzed in different free-living wild animals to assess the genetic diversity and predominant genotypes on each animal species. Samples were taken from the skin and/or nares, and isolates were characterized by spa typing, multilocus sequence typing (MLST) and antimicrobial susceptibility testing. The proportion of MSSA carriers were 5.00, 22.93, 19.78, and 17.67% in Eurasian griffon vulture, Iberian ibex, red deer, and wild boar, respectively (P = 0.057). A higher proportion of isolates (P = 0.000) were recovered from nasal samples (78.51%) than skin samples (21.49%), but the 9.26% of red deer and 18.25% of wild boar would have been undetected if only nasal samples had been tested. Sixty-three different spa types were identified, including 25 new spa types. The most common were t528 (43.59%) in Iberian ibex, t548 and t11212 (15.79% and 14.04%) in red deer, and t3750 (36.11%) in wild boar. By MLST, 27 STs were detected, of which 12 had not been described previously. The most frequent were ST581 for Iberian ibex (48.72%), ST425 for red deer (29.82%), and ST2328 for wild boar (42.36%). Isolates from Eurasian griffon vulture belong to ST133. Host specificity has been observed for the most frequent spa types and STs (P = 0.000). The highest resistance percentage was found against benzylpenicillin (average, 22.2%), although most of the S. aureus isolates were susceptible to all antimicrobial tested. Basically, MSSA isolates were different from those MRSA isolates previously detected in the same animal species.

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BACKGROUND Bovine tuberculosis (bTB) is a chronic infectious disease mainly caused by Mycobacterium bovis. Although eradication is a priority for the European authorities, bTB remains active or even increasing in many countries, causing significant economic losses. The integral consideration of epidemiological factors is crucial to more cost-effectively allocate control measures. The aim of this study was to identify the nature and extent of the association between TB distribution and a list of potential risk factors regarding cattle, wild ungulates and environmental aspects in Ciudad Real, a Spanish province with one of the highest TB herd prevalences. RESULTS We used a Bayesian mixed effects multivariable logistic regression model to predict TB occurrence in either domestic or wild mammals per municipality in 2007 by using information from the previous year. The municipal TB distribution and endemicity was clustered in the western part of the region and clearly overlapped with the explanatory variables identified in the final model: (1) incident cattle farms, (2) number of years of veterinary inspection of big game hunting events, (3) prevalence in wild boar, (4) number of sampled cattle, (5) persistent bTB-infected cattle farms, (6) prevalence in red deer, (7) proportion of beef farms, and (8) farms devoted to bullfighting cattle. CONCLUSIONS The combination of these eight variables in the final model highlights the importance of the persistence of the infection in the hosts, surveillance efforts and some cattle management choices in the circulation of M. bovis in the region. The spatial distribution of these variables, together with particular Mediterranean features that favour the wildlife-livestock interface may explain the M. bovis persistence in this region. Sanitary authorities should allocate efforts towards specific areas and epidemiological situations where the wildlife-livestock interface seems to critically hamper the definitive bTB eradication success.

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Environmental factors may drive tick ecology and therefore tick-borne pathogen (TBP) epidemiology, which determines the risk to animals and humans of becoming infected by TBPs. For this reason, the aim of this study was to analyze the influence of environmental factors on the abundance of immature-stage Ixodes ricinus ticks and on the prevalence of two zoonotic I. ricinus-borne pathogens in natural foci of endemicity. I. ricinus abundance was measured at nine sites in the northern Iberian Peninsula by dragging the vegetation with a cotton flannelette, and ungulate abundance was measured by means of dung counts. In addition to ungulate abundance, data on variables related to spatial location, climate, and soil were gathered from the study sites. I. ricinus adults, nymphs, and larvae were collected from the vegetation, and a representative subsample of I. ricinus nymphs from each study site was analyzed by PCR for the detection of Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum DNA. Mean prevalences of these pathogens were 4.0% ± 1.8% and 20.5% ± 3.7%, respectively. Statistical analyses confirmed the influence of spatial factors, climate, and ungulate abundance on I. ricinus larva abundance, while nymph abundance was related only to climate. Interestingly, cattle abundance rather than deer abundance was the main driver of B. burgdorferi sensu lato and A. phagocytophilum prevalence in I. ricinus nymphs in the study sites, where both domestic and wild ungulates coexist. The increasing abundance of cattle seems to increase the risk of other hosts becoming infected by A. phagocytophilum, while reducing the risk of being infected by B. burgdorferi sensu lato. Controlling ticks in cattle in areas where they coexist with wild ungulates would be more effective for TBP control than reducing ungulate abundance.