964 resultados para Residus animals


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In an increasingly hygiene concerned society, a major barrier to pet ownership is the perceived role of companion animals in contributing to the risk of exposure to zoonotic bacterial pathogens, such as Salmonella. Manifestations of Salmonella can range from acute gastroenteritis to perfuse enteric fever, in both humans and dogs. Dogs are heavily associated with asymptomatic carriage of Salmonella as the microorganism can persist in the lower intestines of this host which can be then excreted into the environment. Studies in to the asymptomatic carriage of Salmonella in dogs are somewhat dated and there is limited UK data. The current UK carriage rate in dogs was investigated in a randomised dog population and it was revealed that the carriage rate in this population was very low with only one household dog positive for the carriage of Salmonella enterica arizonae (0.2%), out of 490 dogs sampled. Salmonella serotypes share phenotypic and genotypic similarities which are captured in epidemiological typing methods. Therefore, in parallel to the epidemiological investigations, a panel of clinical canine (VLA, UK) and human (Aston University, UK) Salmonella isolates were profiled based on their phenotypic and genotypic characteristics; using API 20E, Biolog Microbial ID System, antibiotic sensitivity testing and PFGE, respectively. Antibiotic sensitivity testing revealed a significant difference between the canine and human isolates with the canine group demonstrating a higher resistance to the panel of antibiotics tested. Further metabolic capabilities of the strains were tested using the Biolog Microbial ID System, which reveal no clear association between the two host groups. However, coupled with Principle Component Analysis two canine isolates were discriminated from the entire population on the basis of a high up-regulation of two carbohydrates. API 20E testing revealed no association between the two host groups. A PFGE harmonised protocol was used to genotypically profile the strains. A dendrogram depicting PFGE profiles of the panel of Salmonella isolates was performed where similarities were calculated by Dice coefficient and represented by UPGMA clustering. Clustering of the profiles from canine isolates and human isolates (HPA, UK) was diverse representing a natural heterogeneity of the genus, additionally, no clear clustering of the isolates was observed between host groups. Clustering was observed with isolates from the same serotype, independent of host origin. Host adaption is a common phenomenon in certain Salmonella serotypes, for example S. Typhi in humans and S. Dublin in cattle. It was of interest to investigate potential host adaptive or restricted strains for canine host by performing adhesion and invasion assays on Dog Intestinal Epithelial Cells (DIECs) (WALTHAM®, UK) and human CaCo-2 (HPA, UK) cell lines. Salmonella arizonae and Enteritidis from an asymptomatic dog and clinical isolate, respectively, demonstrated a significantly high proportion of invasion in DIEC in comparison to human CaCo-2 cells and other tested Salmonella serotypes. This may be suggestive of a potential host restrictive strain as their ability to invade the CaCo-2 cell line was significantly lower than the other serotypes. In conclusion to this thesis the investigations carried out suggest that asymptomatic carriage of Salmonella in UK dogs is low however the microorganism remains as a zoonotic and anthroponotic pathogen based on phenotypic and genotypic characterisation however there may be potential for particular serotype to become host restricted as observed in invasion assays

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This is a book for primary school teachers of English written by primary school teachers of English. It brings together the experience and expertise of teachers from around the world to provide a range of stimulating and exciting classroom activities for the primary classroom. There are 50 tried and trusted activities which have been refined and improved over the years by teachers working in diverse contexts and environments. Children will enjoy practising their English through these stimulating and motivating activities. Over 1 000 teachers were contacted and asked to send their favourite activities for teaching English to young learners. The most original and creative activities received were selected for this book. This book grew out of an Aston University - British Council research project called ‘Investigating Global Practices in Teaching English to Young Learners’.

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The pharmacological effects of a number of centrally acting drugs have been compared in euthyroid mice and mice made hyperthyroid by pretreatment with sodium-1-thyroxine. The potencies of two barbiturates, pentobarbitone and thiopentone - as indicated by the duration of their hypnotic actions and their acute toxicities - are increased in hyperthyroid mice. An acutely active uncoupler of phosphorylative oxidation is 2, 4-dinitrophenol, an agent which proved to be a potent hypnotic when administered intracerebrally. An attempt has been made to relate the mechanism of action of the barbiturates to the uncoupling effects of thyroxine and 2, 4-dinitrophenol. The pharmacological effects of chlorpromazine, reserpine and amphetamine-like drugs have also been studied in hyperthyroid mice. After pretreatment with thyroxine, mice show a reduced tendency to become hypothermic after chlorpromazine or reserpine; in fact, under suitable laboratory conditions these agents produce a hyperthermic effect. Yet their known depressant effects upon locomotor activity were not substantially altered. Thus it appeared that depression of locomotor activity and hypothermia are not necessarily correlated, an observation at variance with previously held opinion. These results have been discussed in the light of our knowledge of the role of the thyroid gland in thermoregulation. The actions of tremorine and its metabolite, oxotremorine, have also been examined. Hyperthyroid animals are less susceptible to both the hypothermia and tremor produced by these agents. An attempt is made to explain these observations, in view of the known mechanism of action of oxotremorine and the tremorgenic actions that thyroxine may have. A number of experimental methods have been used to study the anti-nociceptive (analgesic) effects of drugs in euthyroid and hyperthyroid mice. The sites and mechanisms of action of these drugs and the known actions of thyroxine have been discussed.

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In this paper the projected future impact of climate change has been analyzed for the quality of living conditions of the European terrestrial vertebrates (amphibians, reptiles, birds, mammals) in the Carpathian Basin. According to the climate scenarios, warmer and drier climatic conditions are likely to occur in the Carpathian Basin by end of this century. Simultaneous analysis of climate parameters, climate simulations and animal range datasets enables us to evaluate the vulnerability of different European species to regional warming and climate change. The spatial climate analogy technique is used to analyze the estimated rapid change of the wild animals’ habitats and their northward migration. For the reference climate data of Debrecen is considered, and three spatial analogue regions are compared. The results suggest that generally a significant decline in habitats is very likely for most of the analyzed animal groups by the end of the 21st century. The largest rate of decline is estimated for birds. However, living conditions for reptiles may improve in the future due to the warmer and drier climatic conditions, which are favourable for these species.

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This article defines multispecies ethnography and links this scholarship to broader currents within academia, including in the biosciences, philosophy, political ecology, and animal welfare activism. The article is organized around a set of productive tensions identified in the review of the literature. It ends with a discussion of the “ethnographic” in multispecies ethnography, urging ethnographers to bring a “speculative wonder” to their mode of inquiry and writing.

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Acknowledgements Financial support for composing this article was obtained from the Agriculture and Horticulture Development Board (AHDB, Beef and Lamb), UK. Concept of review was also initiated from discussions originating from EU COST Action FA1201, Epiconcept: Epigenetics and Periconception Environment

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Samples (blood or tissue fluid) from 594 arctic foxes (Alopex lagopus), 390 Svalbard reindeer (Rangifer tarandus platyrhynchus), 361 sibling voles (Microtus rossiaemeridionalis), 17 walruses (Odobenus rosmarus), 149 barnacle geese (Branta leucopsis), 58 kittiwakes (Rissa tridactyla), and 27 glaucous gulls (Larus hyperboreus) from Svalbard and nearby waters were assayed for antibodies against Toxoplasma gondii using a direct agglutination test. The proportion of seropositive animals was 43% in arctic foxes, 7% in barnacle geese, and 6% (1 of 17) in walruses. There were no seropositive Svalbard reindeer, sibling voles, glaucous gulls, or kittiwakes. The prevalence in the arctic fox was relatively high compared to previous reports from canid populations. There are no wild felids in Svalbard and domestic cats are prohibited, and the absence of antibodies against T gondii among the herbivorous Svalbard reindeer and voles indicates that transmission of the parasite by oocysts is not likely to be an important mechanism in the Svalbard ecosystem. Our results suggest that migratory birds, such as the barnacle goose, may be the most important vectors bringing the parasite to Svalbard. In addition to transmission through infected prey and carrion, the age-seroprevalence profile in the fox population suggests that their infection levels are enhanced by vertical transmission.

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It is apparent that most of the techniques that make use of ionising radiation in human medical practices are now being applied in veterinary medicine. Steps are being taken by the IAEA to provide guidance for humans involved in such practices, but there appears to be no international initiative that considers the protection or welfare of the animal as a patient. There is therefore a risk that the deliberate exposure of an animal, particularly in the therapeutic application of radiation, could do more harm than good. In the light of recent developments in dosimetric modelling and the application of known effects of radiation on different types of animals, for the purposes of the protection of biota in an environmental context, it is argued that it would be sensible now to start a serious consideration of this issue. Some suggestions are made with regard to a number of areas that could be considered further, both specifically and with regard to the field of radiological protection as a whole.

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It is apparent that most of the techniques that make use of ionising radiation in human medical practices are now being applied in veterinary medicine. Steps are being taken by the IAEA to provide guidance for humans involved in such practices, but there appears to be no international initiative that considers the protection or welfare of the animal as a patient. There is therefore a risk that the deliberate exposure of an animal, particularly in the therapeutic application of radiation, could do more harm than good. In the light of recent developments in dosimetric modelling and the application of known effects of radiation on different types of animals, for the purposes of the protection of biota in an environmental context, it is argued that it would be sensible now to start a serious consideration of this issue. Some suggestions are made with regard to a number of areas that could be considered further, both specifically and with regard to the field of radiological protection as a whole.

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Understanding the exploration patterns of foragers in the wild provides fundamental insight into animal behavior. Recent experimental evidence has demonstrated that path lengths (distances between consecutive turns) taken by foragers are well fitted by a power law distribution. Numerous theoretical contributions have posited that “Lévy random walks”—which can produce power law path length distributions—are optimal for memoryless agents searching a sparse reward landscape. It is unclear, however, whether such a strategy is efficient for cognitively complex agents, from wild animals to humans. Here, we developed a model to explain the emergence of apparent power law path length distributions in animals that can learn about their environments. In our model, the agent’s goal during search is to build an internal model of the distribution of rewards in space that takes into account the cost of time to reach distant locations (i.e., temporally discounting rewards). For an agent with such a goal, we find that an optimal model of exploration in fact produces hyperbolic path lengths, which are well approximated by power laws. We then provide support for our model by showing that humans in a laboratory spatial exploration task search space systematically and modify their search patterns under a cost of time. In addition, we find that path length distributions in a large dataset obtained from free-ranging marine vertebrates are well described by our hyperbolic model. Thus, we provide a general theoretical framework for understanding spatial exploration patterns of cognitively complex foragers.

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Understanding the exploration patterns of foragers in the wild provides fundamental insight into animal behavior. Recent experimental evidence has demonstrated that path lengths (distances between consecutive turns) taken by foragers are well fitted by a power law distribution. Numerous theoretical contributions have posited that “Lévy random walks”—which can produce power law path length distributions—are optimal for memoryless agents searching a sparse reward landscape. It is unclear, however, whether such a strategy is efficient for cognitively complex agents, from wild animals to humans. Here, we developed a model to explain the emergence of apparent power law path length distributions in animals that can learn about their environments. In our model, the agent’s goal during search is to build an internal model of the distribution of rewards in space that takes into account the cost of time to reach distant locations (i.e., temporally discounting rewards). For an agent with such a goal, we find that an optimal model of exploration in fact produces hyperbolic path lengths, which are well approximated by power laws. We then provide support for our model by showing that humans in a laboratory spatial exploration task search space systematically and modify their search patterns under a cost of time. In addition, we find that path length distributions in a large dataset obtained from free-ranging marine vertebrates are well described by our hyperbolic model. Thus, we provide a general theoretical framework for understanding spatial exploration patterns of cognitively complex foragers.

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To the Editor—We thank Bonten and Mevius for their interest in our systematic review [1]. In their letter, they disagree with our finding that whole-bacterium transmission (WBT) of expanded-spectrum cephalosporin-resistant (ESCR) Escherichia coli between food-producing animals and humans likely contributes to the burden of human extraintestinal infections. We respectfully argue against 2 assumptions that underlie their assertion.

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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.