Dissertations / Theses: 'Animal Microbiology'

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Racicot, Bergeron Catherine. "Food animal reservoir for extraintestinal pathogenic «Escherichia coli» causing human infections." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104886.

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Studies of extraintestinal infections caused by genetically related strains of Escherichia coli among unrelated people have demonstrated the epidemic potential of this group of bacteria. These related extraintestinal pathogenic E. coli (ExPEC) may have a common source. Our group recently described how retail meat, particularly chicken, may be a reservoir for ExPEC causing human urinary tract infections (UTIs). By moving upstream on the farm to fork continuum, this study tests whether the reservoir for ExPEC is in food animals themselves. A total of 824 geographically and temporally matched E. coli isolates from cecal contents of slaughtered food animals (n=349) and human UTI (n=475) sources were compared. Using 6 different typing methods, an evolutionary relationship was observed between E. coli isolates from the food animal reservoir and human UTI. Moreover, chicken was the predominant animal species from where the related isolates originated. Using an evolutionary model, chicken was determined to be the most likely source of the human UTI isolates. This study confirmed that an animal reservoir, principally in chicken, may exist for ExPEC causing community-acquired UTI.
Les études portant sur les infections extra-intestinales causées par des souches d'Escherichia coli génétiquement apparentées, chez des personnes non reliées entre elles, ont démontré le potentiel épidémique de ce groupe de bactéries. Ces souches d'E. coli pathogènes extra-intestinales (ExPEC) apparentées auraient possiblement une source commune. Notre groupe a récemment décrit comment la viande de détail, plus particulièrement le poulet, pourrait être un réservoir d'ExPEC responsables d'infections urinaires (IUs) chez les humains. En se déplaçant plus en amont dans le continuum de la ferme à la fourchette, cette étude teste si le réservoir d'ExPEC se trouve dans les animaux de production eux-mêmes. Un total de 824 isolats d'E. coli de provenances géographique et temporelle communes, prélevés dans le contenu caecal d'animaux abattus (n=349) et de cas d'IU humaine (n=475) ont été comparés. Par l'utilisation de 6 différentes méthodes de typage, une relation évolutionnaire a été observée entre les isolats d'E. coli provenant du réservoir animal et d'IU humaine. De plus, le poulet était l'espèce animale prédominante parmi les isolats parentés. L'utilisation d'un modèle évolutionnaire a permis de déterminer que le poulet est la source la plus probable des isolats d'IU humaine. Cette étude a confirmé qu'un réservoir animal, principalement chez le poulet, pourrait exister pour les ExPEC qui causent des IUs acquises en communauté.

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Albergaria, Furtado Semedo Miguel. "Animal Waste and Antibiotic Impacts on Microbial Denitrification in Terrestrial and Aquatic Ecosystems." W&M ScholarWorks, 2019. https://scholarworks.wm.edu/etd/1582642568.

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The global increase in livestock and poultry production observed in the last decades has led to an increase in animal waste generated. The animal waste contains high levels of nitrogen and may carry antibiotics that can disturb important microbial activities such as denitrification in terrestrial and aquatic ecosystems. Disturbances of microbial denitrification can have detrimental consequences to environmental health. In the terrestrial environment, denitrification is an important source and sink of N2O, a potent greenhouse gas in the atmosphere. In aquatic ecosystems, denitrification is a dominant NO3- removal pathway, contributing to prevent eutrophication. The overall goal of this dissertation is to evaluate the impacts of animal waste and potential antibiotic exposure on microbial communities responsible for denitrification in terrestrial and aquatic ecosystems. To achieve this goal, a combined approach of measuring activity rates and performing a molecular characterization of the microbial communities was used. In Chapter 2, the microbial community changes associated with the impacts of acute antibiotic exposure on denitrification were evaluated in soil microcosms. Antibiotic exposure caused a significant increase in N2O production from denitrification. This increase was paralleled with a greater ratio of fungi:bacteria abundance and lower abundances of particular taxa with N2O reduction capacity. In Chapter 3, the impacts of animal manure and antibiotic contamination on N2O fluxes and the abundance of denitrification genes were investigated in soil mesocosms. N2O fluxes in soils treated with manure fertilizer and tetracycline were considerably higher than in control soils. The manure fertilization and antibiotic exposure had diverse effects on different bacterial taxa responsible for N2O production. In Chapter 4, the denitrification activity and microbial community structure in tidal creek sediments impacted by wastewater discharge from a poultry processing plant were evaluated through a field survey and a microcosm experiment. Denitrification rates were inhibited in the location affected by the wastewater discharge. This decrease in denitrification activity was associated with changes in the microbial community structure, such as a lower relative abundance of bacterial taxa carrying denitrification genes and lower abundance of N2O reducing bacteria. In Chapter 5, the abundance and diversity of antibiotic resistance genes were evaluated in a tidal creek impacted by wastewater discharge from a poultry processing plant. The numbers of antibiotic resistance genes were higher in the location closer to the wastewater discharge, suggesting an historic antibiotic exposure associated with the activity of the poultry processing plant. Overall, this work provides new knowledge of the impacts of animal waste and antibiotics on N2O emissions in terrestrial ecosystems and microbial NO3- removal in aquatic ecosystems. This dissertation emphasizes the functional importance of microbial communities to ecosystem health and their responses to anthropogenic disturbance.

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Lenati, Raquel F. "Ecology, biological characterization and development of an animal model for Enterobacter sakazakii." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27876.

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Enterobacter sakazakii is an emerging foodborne pathogen which has been linked to a number of outbreaks associated with the consumption of powdered infant formula, especially in low-birth-weight and premature infants. Very little research has focused on molecular characterization of this organism and the mechanism(s) by which it causes disease in humans. In this study, a collection of 260 isolates of E. sakazakii were assessed by phenotypic and genotypic tests. The use of 16S rDNA analysis showed an 82% identity amongst the strains tested. Interestingly, 14 strains originally identified as E. sakazakii by phenotypic characterization, were found to be other species or genera. Among the molecular typing methods, pulsed-field gel electrophoresis was found to be more discriminatory than automated ribotyping. Furthermore, the theory that expressed human breast milk, if contaminated with E. sakazakii, would support E. sakazakii growth at 10, 23 and 37°C, was investigated. It was found that the intrinsically ascribed antimicrobial properties of breast milk do not appear to inhibit the growth of this foodborne pathogen in vitro. Lastly, we assessed six animal species to find an animal model that would be well suited to conduct further studies on the virulence of E. sakazakii infection. Young (chicks, gerbils, guinea pigs, pigs, rabbits) and neonatal (gerbils, rats) animals were orally challenged with E. sakazakii at a level of 109 cells. Of all the animal models tested, it appears that the neonatal gerbil may be most suitable for further studies.

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Sanders, Jon G. "Disentangling the Coevolutionary Histories of Animal Gut Microbiomes." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:17463127.

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Animals associate with microbes in complex interactions with profound fitness consequences. These interactions play an enormous role in the evolution of both partners, and recent advances in sequencing technology have allowed for unprecedented insight into the diversity and distribution of these associations. However, our understanding of the processes generating those patterns remains in its infancy. Here, I explore variation in microbiomes across two animal lineages—ants and mammals—to tease apart the role of these process in the evolution of gut microbiota. First, I explore patterns of phylogenetic correlation in gut microbiota of herbivorous Cephalotes ants and hominid apes. By examining the sensitivity of phylogenetic correlation to analytical parameters, I show that these outwardly similar patterns are likely to be the result of very different processes in each host lineage. Next, I examine in more depth the interacting effects of diet and phylogeny on the structure of baleen whale microbiomes. Whales consume a diet that differs dramatically from that of their closest extant relatives, the herbivorous artiodactyls. I use a combination of marker gene and shotgun metagenomic sequencing to show that a phylogentically conserved host trait, the multichambered gut, leads to functional and taxonomic similarities of whale gut microbiomes to those of their herbivorous ancestors via the fermentation of animal polysaccharides in the exoskeletons of their prey. Finally, I return to ants to examine how major shifts in the nature of gut microbial association correspond to host ecology. Using measures of absolute bacterial abundance, rather than diversity, I test the hypothesis that evolution of symbiosis with microbes has facilitated ants’ dominance of tropical rainforest canopies. Surprisingly, I find differences in the abundance of gut bacteria in different ant lineages that span many orders of magnitude, suggesting that evolutionary transitions in the functional role of symbiosis in this animal lineage correspond not only to changes in the diversity of these associations, but to changes in kind. The results of these studies help to clarify the roles of history and selection in structuring animal gut microbiota, hinting that the interaction of these factors may fundamentally differ between animal lineages.
Biology, Organismic and Evolutionary

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Curtis, Steven C. "Microbial Ecology of an Animal Waste-Fueled Induced Blanket Reactor." DigitalCommons@USU, 2006. https://digitalcommons.usu.edu/etd/5534.

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Use of an induced blanket reactor (IBR) to break down organic matter into methane is a financially attractive method to reduce the environmental impact of animal or industrial waste. In order to better understand the biological processes involved with the conversion of waste to biogas by an IBR, it is necessary to gain a better understanding of the microorganisms and their roles in the reactor. Molecular techniques based on the isolation of 16S rDNA were used in order to avoid the limitations posed by conventional culture-based techniques. Total DNA was extracted and amplified using universal primers specific to eubacteria and archaea with the purpose of identifying the dominant microorganisms in the IBR. The amplified DNA was separated based on its sequence composition by denaturing gradient gel electrophoresis (DGGE). Several bands were then excised, cloned, and sequenced, in order to characterize the phylogenetic affiliation of many of the microorganisms and create a useful molecular fingerprint. By using this approach, close relatives of several microorganisms that are typical in anaerobic digestion have been identified, including species of Clostridium, Flavobacterium, Bacteroides, Spirochaeta, Methanobrevibacter, and Methanosarcina. Several species were also identified whose role in the reactor is not completely understood, consisting of relatives of Dehalococcoides, Planctomyces, Aequorivita, and Sedimentibacter species. The information obtained in this project may enable refinements that promote desirable reactions and enhance reactor efficiency.

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Chen, Lei. "The impact of herbal saponins on gut microflora in animal models." HKBU Institutional Repository, 2014. https://repository.hkbu.edu.hk/etd_oa/55.

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Human gut harbors 100 trillion microbial organisms that is intrinsically linked to individual’s health and diseases, including cancer. Food fiber and phytochemicals such as polyphenols are considered as prebiotic-like dietary modifiers. They can influence the gut microbial communities, and in turn to modulate disease outcome and drug responses of the host. Saponins belong to a family of phytochemicals commonly found in many medicinal and edible plants. Herbal saponins have raised keen interest among scientists for their health-promoting effects, but have not been investigated for their potential as prebiotics. Gynostemma pentaphyllum (Gp) is riched in triterpenoid saponins and has been consumed in China and other part of the world as an herbal tea and as a folk medicine. In our lab, we have demonstrated that Gp possesses strong anticancer and anti-inflammatory effects. Whether Gp possesses prebiotic property and whether gut microbiota plays any part of the anticancer effect of Gp are the questions addressed in the present study. Thus, we hypothesized that Gp saponins (GpS) might modulate the gut microbiota, which in turn enhance its anticancer activities. In the study, the gut microbiome analysis were carried out using two main techniques, neamly the enterobacterial repetitive intergenic consensus (ERIC-PCR) and 16S pyrosequencing approaches. Both xenograft nude mice and Apcmin/+ mice were employed as the animal models to investigate the interaction between the herbal saponins and the gut microbiota in the host. Athymic nude mice have been employed for tumorigenic research for decades, however, the relationships between the gut microbiome and host’s response to the grafted tumors and drug treatments are unexplored. For the first part of the thesis, we investigated the relationship between the gut microbiota and grafted tumor in the nude mice under the treatment of Gp saponins. Partial least squared discriminant analysis (PLS-DA) of ERIC-PCR data showed that the microbiota profile of xenograft nude mice departed from that of the nonxenograft mice. However, prolonged treatment of GpS seems to realign the fecal microbiota with the pretreatment control. Pyrosequencing data reiterated the differences in fecal microbiome between the nonxenograft and xenograft animals. GpS treatment had a much stronger impact on the phylotypes of the xenograft than the nonxenograft mice. In addition, GpS treatment markedly induced the relative abundance of Clostridium cocleatum and Bacteroides acidifaciens, for which the beneficial effects on the host have been well documented. ApcMin/+ colorectal cancer mouse model was further employed for the investigation of the association of the gut microbiota and cancer occurred inside the gut, which was a more direct site to interact with the gut microbiota. In the ApcMin/+ mouse model, we found distinct difference of fecal microbiome between the ApcMin/+ and the wild-type littermates. GpS treatment significantly reduced the number of intestinal polyps. GpS also increased the ratio of Bacteroidetes/Firmicutes and reduced the sulfate- and sulfur-reducing bacteria lineage and potential opportunistic pathogens, which might cause certain deleterious effects to the host. The impact of GpS on the gut mucosal environment was also examined. We found GpS treatment improved the gut barrier function by increasing the numbers of Paneth cells, goblet cells, up-regulating the expression of E-cadherin and down-regulating the expression of N-cadherin in the intestine. In addition, GpS treatment down-regulated the protein expression of beta-catenin and p-STAT3. Furthermore, higher levels of anti-inflammatory and tissue repair-related cytokines as well as Arginase I, but lower level of iNOS expression were found in GpS-treated ApcMin/+ mice, indicating increased anti-inflammatory macrophage phenotype M2 (associated with tissue repair) and reduced proinflammatory phenotype M1. Furthermore, in addition to GpS, other herbal saponins also showed prebiotic-like effects in C57BL/6 mice. In summary, this study provides first hand evidence for the impact of herbal saponins on the gut microbial ecosystem and new insight into mechanisms responsible, at least in part, for the activities of GpS. We demonstrate that tumor growth induce intestinal dysbiosis. GpS treatment can inhibit tumor progression and concurrently alter the microbiome by increasing symbionts and/or decreasing pathobionts, which may contribute to its chemopreventive effect against tumorigenesis. Herbal saponins showing prebiotic-like effects may be used for improving the health of the host by manipulation of the gut microbiota.

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Cole, Stephen Douglas. "Genetic Diversity of the Pathogen Streptococcus parauberis Isolated from Bovine and Piscine Hosts." W&M ScholarWorks, 2011. https://scholarworks.wm.edu/etd/1539626906.

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Eckstrom, Korin. "Evaluating The Resistome And Microbial Composition During Food Waste Feeding And Composting On A Vermont Poultry Farm." ScholarWorks @ UVM, 2018. https://scholarworks.uvm.edu/graddis/886.

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While commonly thought of as a waste product, food scraps and residuals represent an important opportunity for energy and nutrient recapture within the food system. As demands on production continue to increase, conservation of these valuable resources has become a priority area. In the wake of new legislation in Vermont, Act 148, the Universal Recycling Law, the fate of microbial species in food waste, scraps and residuals is increasingly important. The presence of antimicrobial resistance genes in all types of foods calls for an increased need to estimate risk of antibiotic resistance transfer and maintenance across all segments of food production and distribution systems, from farm to fork. Specifically, the fate of antibiotic resistance genes (ARGs) in these co-mingled food wastes has not been sufficiently characterized; as legislative programs increase in popularity, surveillance of these materials is pressing and should be documented to assess the risk and potential measures for mitigation and management as we approach commercial scales of implementation Previous studies have relied on a combination of targeted techniques, such as 16S rRNA sequencing and qPCR on a specific subset of ARGs; however, these may not cover the full extent of resistance or microorganisms of concern in any given sample. As sequencing technologies improve and costs continue to drop, more comprehensive tools, such as shotgun metagenomic sequencing, can be applied to these problems for both surveillance and novel gene discovery. In this study, we leveraged the increased screening power of the Illumina HiSeq and shotgun metagenomic sequencing to identify and characterize ARGs, microbial communities, and associated virulence factors of food scraps, on-farm composts, and several consumer products. Isolates were also screened for antibiotic resistance to demonstrate the functionality of ARGs identified. The resistome, microbiome, and virulence genes were characterized in all samples. Fifty unique ARGs were identified that spanned 8 major drug classes. Most frequently found were genes related to aminoglycoside, macrolide, and tetracycline resistance. Additionally, 54 distinct virulence factors and 495 bacterial species were identified. Virulence factors were present across the farm setting and mainly included gene transfer mechanisms, while bacteria clustered distinctly into site and farm, as well as separate on farm niches. The relationship between these categories was also assessed by both Pearson correlation and co-inertia analysis, with the most significant relationship being between ARGs and virulence factors (P = 0.05, RV = 0.67). While limited in this study, these patterns reinforce the finding that spread of antibiotic resistance genes may be dependent on the virulence factors present enabling transfer, rather than total microbial community composition.

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Mandal, Rabindra Kumar. "Genetic Determinants of Salmonella and Campylobacter Required for In Vitro Fitness." Thesis, University of Arkansas, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10249279.

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Non-typhoidal Salmonella (NTS) and Campylobacter play a major role in foodborne illness caused by the consumption of food contaminated by pathogens worldwide. A comprehensive understanding of the genetic factors that increase the survival fitness of these foodborne pathogens will effectively help us formulate mitigation strategies without affecting the nutrition ecology. The objective of this study was to identify the genetic determinants of Salmonella and Campylobacter that are required for fitness under various in vitro conditions. For the purpose, we used a high throughput Transposon sequencing (Tn-seq) that utilizes next generation sequencing (NGS) to screen hundreds of thousands of mutants simultaneously. In Chapter 1, we reviewed the technical aspects of different Tn-seq methods along with their pros and cons and compressive summary of recently published studies using Tn-seq methods. In Chapter 2, we exposed complex Tn5 library of Salmonella Typhimurium 14028S (S. Typhimurium) to the mimicked host stressors in vitro conditions. Such as low acidic pH (pH 3) found in the stomach, osmotic (3% NaCl) and short chain fatty acid (SCFAs, 100 mM Propionate) found in intestine, and oxidation (1mM H2O2) and starvation (12-day survival in PBS) found in macrophage. There was an overlapping set of 339 conditionally essential genes (CEGs) required by S. Typhimurium to overcome these host stressors. In Chapter 3, we screened of S. Typhimurium Tn5 library for desiccation survival. Salmonella spp. is the most notable and frequent cause of contamination in low-water activity foods. We identified 61 genes and 6 intergenic regions required for fitness during desiccation stress. In Chapter 4, the essential genome of Campylobacter jejuni (C. jejuni) NCTC 11168 and C. jejuni 81-176 was investigated using Tn-seq. We identified 166 essential protein-coding genes and 20 essential transfer RNA (tRNA) in C. jejuni NCTC 11168 which were intolerant to Tn5 insertions during in vitro growth. The reconstructed library C. jejuni 81-176 had 384 protein coding genes with zero Tn5 insertions. The genetic determinants Salmonella and Campylobacter identified in this study have high potential to be explored as food safety intervention, therapeutic and vaccine target to curb the spread of the foodborne pathogens making world a safer place.

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Fitzgerald, Collette Catherine. "The use of high resolution genotyping techniques to investigate the genotypic diversity of Campylobacter spp. isolated from human, animal and environmental sources." Thesis, Lancaster University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264781.

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Lakay, Francisco Martin. "Fungal enzymes as animal feed additives." Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52280.

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Thesis (MSc)--Stellenbosch University, 2001.
ENGLISH ABSTRACT: The use of fungal enzymes as ruminant feed digestibility enhancers was investigated. Currently, ruminants may not digest 38 to 80 % of fibrous forages' content. A renewed interest in the potential of feed enzymes for ruminants was prompted by the high costs of livestock production, together with the availability of newer enzyme preparations. Direct application of enzyme preparations can improve in vitro dry matter (DM) and neutral detergent fibre (NDF) degradation, indicating that direct-fed fibrolytic enzymes may be effective in enhancing in vivo digestion of forages. Two commercial enzyme products, Fibrozyme and Celluclast, and fungal extracellular enzyme extracts from Aureobasidium pullulans, Trichoderma reesei, Aspergillus aculeatus, and Thermomyces lanuginosus were evaluated for enhancing in vitro feed digestibility. Fibrozyme addition to both wheat straw and lucerne hay did not improve their in vitro digestibilities, even after a two hour pre-incubation period. The four fungal enzyme extracts did not enhance wheat straw's digestibility, but marginal increases were evident for lucerne hay. Celluclast addition resulted in marginal increases in the digestibility of both oat hay and oat silage, with no enhanced effect on lucerne hay and NaOH-treated wheat straw. No relationship could be found between the level of enzyme activity and the degree of feed digestion in the in vitro assay. Enzyme hydrolysis with Celluclast, in the absence of rumen fluid, gave more conclusive results. All the feed samples tested showed a positive response to Celluclast addition, even the less digestible feeds, namely sugarcane bagasse and wheat straw. In vitro results show that the assays were unsuccessful, because almost all of the experiments conducted showed inconclusive results. Alternative feed evaluation assays, which include the in vivo, in sacco and in situ methods of analysis, as well as gas production measurement and in vitro analysis with the DAISyII system, should be evaluated. A more detailed study of feed digestibility should be motivated by determining which feeds are hydrolysable, their chemical composition, i.e. how accessible the feeds are, and also evaluation of feed mixtures. The enzyme supplements also need to be evaluated for optimum temperature and pH, as well as the compilation of enzyme cocktails.
AFRIKAANSE OPSOMMING: Die gebruik van swamensieme om die verteerbaarheid van herkouervoere te verhoog, is ondersoek. Tussen 38 en 80 % van veselagtige voere se inhoud is tans onverteerbaar. 'n Hernieude belangstelling in die potensiaal van voerensieme vir herkouers word deur die hoë koste van veeproduksie, asook die beskikbaarheid van nuwe ensiempreparate gedryf Direkte byvoeging van ensiempreparate kan die in vitro droëmateriaal (DM) en neutrale onoplosbare vesel (NOV) vertering verbeter, wat daarop dui dat fibrolitiese ensieme wat direk gevoer word, effektief mag wees tydens die in vivo vertering van voer. Twee kommersiële ensiemprodukte, Fibrozyme en Celluclast, en die vier ekstrasellulêre ensieme van vier swamme, naamlik Aureobasidium pullulans, Trichoderma reesei, Aspergillus aculeatus, en Thermomyces lanuginosus is vir hul vermoë om die in vitro verteerbaarheid van voere te verbeter getoets. Byvoeging van Fibrozyme by beide koringstrooi en lusernhooi het geen verbetering in hulonderskeie in vitro verteerbaarheid tot gevolg gehad nie, selfs nie eens na 'n twee uur vooraf inkubasieperiode nie. Koringstrooi se verteerbaarheid is nie verbeter deur die byvoeging van die vier swam-ensiempreparate nie, maar 'n minimale verbetering is wel waargeneem in die verteerbaarheid van lusernhooi. Byvoeging van Celluclast het 'n minimale verbetering in beide hawerhooi en hawerkuilvoer se verteerbaarheid tot gevolg gehad, maar geen effek op lusernhooi of NaOH-behandelde koringstrooi se verteerbaarheid nie. Geen verwantskap is tussen die vlak van ensiemaktiwiteit en die mate van vertering tydens die in vitro toets gevind nie. Ensiematiese afbraak met Celluclast, in die afwesigheid van rumenvloeistof, het meer konkrete resultate gelewer. Al die voermonsters het 'n positiewe respons op die byvoeging van Celluclast getoon, selfs ook die minder verteerbare voere, nl. suikerrietbagasse en koringstrooi. In die wyer konteks was die resulate van die in vitro verteringstoetse egter onbeduidend as gevolg van groot variasie in die metings. Alternatiewe voerontledingstoetse, wat moontlik beter resultate mag lewer, sluit in in vivo, in sacco en in situ analises, asook die meting van gasproduksie en in vitro analise met die DAISyII sisteem. 'n Meer uitgebreide studie van voerverteerbaarheid wat die bepaling van die afbraak van voere, hul chemiese samestelling, met ander woorde toeganklikheid van voere, en die ondersoek van voermengsels behels, behoort aandag te geniet. Die ensiemmengsels behoort ook ten opsigte van samestelling, optimum temperatuur en pH ondersoek teword.

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Cardozo, Marita Vedovelli [UNESP]. "Salmonella spp. e Clostridium perfringens em farinhas de origem animal utilizadas na fabricação de rações e avaliação de aditivo na inibição de patógeno." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/94934.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O processamento dos resíduos gerados durante a produção avícola origina subprodutos que podem ser utilizados na alimentação animal resultando em rações economicamente viáveis. Entretanto, a qualidade dos ingredientes que compõem a ração é de extrema importância, pois o alimento pode veicular diversos patógenos. Dessa forma foi desenvolvido o presente estudo, com o objetivo de avaliar através dos métodos bacteriológicos convencionais a qualidade microbiológica de Farinha de Vísceras (FV), Farinha de Sangue e Penas (FSP) e Farinhas de Carne e Ossos (FCO) no que se refere a contaminação pelos microrganismos Salmonella spp. e Clostridium perfringens, bem como testar a eficiência para inibição microbiana de um produto químico a base de formaldeído e ácidos orgânicos. Das 180 amostras de farinhas analisadas, 71 (39,4%) apresentaram resultado positivo em relação à presença de C. perfringens, e 41 (22,8%) apresentaram resultado positivo quanto à presença de Salmonella spp. O produto a base de formaldeído e ácidos orgânicos mostrou-se eficiente na inibição de C. perfringens pois as contagens diminuíram significativamente após 24 horas e, após cinco dias foi observado ausência total do microrganismo nas amostras testadas. A presença dos patógenos Salmonella spp. e C. perfringens em todos os tipos de farinhas analisadas evidencia que este sub-setor necessita de aportes tecnológicos, além de serem responsáveis por perdas econômicas aos produtores e um risco à saúde pública. A eficiência do produto químico testado mostra que existe forma de inibir o crescimento do C. perfringens, um grande avanço para a avicultura
The processing of the waste generated during production originates poultry products that can be used in animal feed rations resulting in economically viable. However, the quality of the ingredients in the diet is extremely important, because the food may carry various pathogens. Thus the present study was developed with the aim to assess by conventional bacteriological methods the microbiological quality of poultry offal meal (POM), Blood Meal and Feather (FSP) and Meat and Bone meal (MBM) with regard to contamination by pathogens Salmonella spp. and C. perfringens, as well as testing the efficiency of the chemical basis of formaldehyde and organic acids. Of 180 flour samples analyzed, 71 (39.4%) were positive for the presence of Clostridium perfringens, and 41 (22.8%) were positive for the presence of Salmonella spp. The base product of formaldehyde and organic acids proved effective in inhibiting C. perfringens as the counts decreased significantly after 24 hours, and after five days was observed total absence of the microorganism in the samples tested. The presence of the pathogens Salmonella spp. e C. perfringens in all kinds of flours analyzed shows that this sub-sector needs technological contributions, besides being responsible for economic losses to producers and a public health risk. The efficiency of the chemical test shows that there is no way to inhibit the growth of C. perfringens, a major breakthrough for the poultry industry

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Sakate, Ricardo Ichiro. "Prevalência, epidemiologia, caracterização sorológica e molecular de Listeria monocytogenes isoladas na criação intensiva de Novilhos Superprecoces e em abatedouros frigoríficos no Estado de São Paulo." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-08082017-155252/.

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O Brasil é um dos principais exportadores de carne bovina. A maioria do gado é criada a pasto, porém uma parte já é confinada, como na criação de Novilhos Superprecoces. Este confinamento pode favorecer a contaminação por L. monocytogenes (Lm) do rebanho, bactéria responsável pela listeriose, doença que provoca aborto, neuropatias e gastrenterites. Com isto, pesquisou-se a presença e características sorotípicas e moleculares de Lm durante o confinamento de cinco raças de novilhos e em suas carcaças no frigorífico A, assim como amostras de carcaças, utensílios, equipamentos e ambiente em outro frigorífico (B). Foram utilizadas para tipar as cepas técnicas de sorotipagem por multiplex PCR, soroaglutinação e PFGE. Nenhuma Lm foi isolada nas 645 amostras do confinamento, sendo 13/48 carcaças dos novilhos, assim como amostras de piso e parede da câmara fria positivas para Lm no frigorífico A. Das 516 amostras do frigorífico B, 27 continham Lm, sendo a maioria proveniente da área limpa. Verificou-se que os sorotipos 1/2c e 4b foram os mais freqüentes no frigorífico A e o 1/2b e 1/2c no frigorífico B. A análise por PFGE forneceu 15 perfis Ascl, 13 Apal e 21 perfis compostos, caracterizando sete grupos clonais. Nesta cadeia produtiva de carne o principal ponto crítico para Lm está na área limpa do frigorífico e que cepas de mesmos grupos clonais puderam ser encontrados em ambos frigoríficos, assim como em áreas distintas do frigorífico B, demonstrando o alto poder de disseminação destas cepas. Portanto, estes resultados podem auxiliar no desenvolvimento de programas de boas práticas e HACCP para prevenir ou eliminar a contaminação por este patógeno.
Brazil is one of the most important beef producer/exporter country worldwide. The majority of the cattle is raised extensively, but some of them are feedloted. Confinement conditions can stress the animals and favor the contamination and proliferation for Listeria monocytogenes (Lm), agent of listeriosis which causes abortion, stillbirths, nervous dysfunctions and gastroenteritis. The aim of this study was to verify the presence of this microorganism and its molecular and serotype characteristics. Two groups of samples were analyzed: first, during the confinement of five different breeds of steers and on their carcasses (abattoir A). Second, at the slaughter and processing of other groups of beef cattle (abattoir B). The Lm strains were serotyped with commercial antisera and by multiplex PCR, and subtyped by PFGE. No Lm was found among the 645 samples of feces, environment, feed and water during the confinement, but 13/48 of the refrigerated carcasses were contaminated, as well as the floor and the wall of the cold room at the abattoir A. Amongst the 516 samples of slaughter and processing environments, carcasses, utensils and equipment collected from abattoir B, 27 harbored Lm, being the majority from the c1ean area. Serotype 1/2b and 4b were the most frequent Lm serotypes in the carcasses of the steers in abattoir 1, and 1/2b and 1/2c in the abattoir B. The molecular typing by PFGE resulted in 15 Ascl and 13 Apal profiles, and 21 composite profiles, resulting in seven clonal groups. In these beef production chains the most important critical point for Lm contamination is the c1ean area of meat processing. Same clonal groups could be isolated in both abattoirs and in different areas on abattoir B, demonstrating high dissemination capability of these strains. Therefore, these results could aid the development of good manufacturing practices and HACCP, to prevent or eliminate the contamination for this pathogen.

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Lee, Bill. "Preclinical antimicrobial drug discovery : development and evaluation of a platform for high-throughput screening in vitro and an immunocompromised animal model." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=100745.

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The incidence of infections caused by antibiotic-resistant bacteria and fungi is rising rapidly. Once considered as little more than a nuisance, antibiotic resistance has become a serious threat. The mortality rate for some infections is approaching that of the pre-antibiotic era. New antimicrobials are needed urgently. Prior to the introduction of any new antimicrobial, comprehensive toxicity and efficacy profiles are assessed in preclinical studies. This thesis focuses on two key stages of preclinical antimicrobial drug development, specifically compound screening in vitro and animal efficacy testing in vivo. We developed a sensitive colorimetric platform with high-throughput capacity for the rapid screening of candidate antimicrobials. This platform could be adapted to assess compounds targeting a range of bacteria, fungi (such as Candida albicans), and protozoan parasites (such as Leishmania major). When this assay was modified to measure minimum inhibitory concentrations (MICs) for bacteria, 100% agreement within one dilution was achieved compared to the gold-standard method. A novel antifungal compound was taken forward to animal testing in an immunocompromised mouse model. We demonstrated herein that a histone deacetylase inhibitor in combination with an imidazole can synergise to produce a potent antifungal effect. A dose-dependent response, defined as a lower fungal burden and a higher survival rate, was achieved with increasing concentrations of the novel inhibitor.

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Serrano, Figueroa Luis O'mar. "A study on amphiphilic siderophore detection, structure elucidation and their iron-mediated vesicle self-assembly." Thesis, Montana State University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3708788.

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Soap Lake, located in Washington State, was the subject of an NSF funded Microbial Observatory and is a naturally occurring saline and alkaline lake. Several organisms inhabiting this lake have been identified as producers of siderophores that are unique in structure. Two isolates SL01 & SL28 were the focus of this study of siderophore production, structure elucidation and vesicle self-assembly. Bacterial isolates, enriched from Soap Lake sediment and water samples, were screened for siderophore production. Siderophore production was confirmed through the chrome azurol S (CAS) agar plate method. Isolates SL01 and SL28 were found to produce relatively high concentrations of siderophores in liquid medium. Extraction was performed by the methanol/water protocol in Varian cartridges and siderophore purification was done on HPLC with a 0-70% acetonitrile gradient. Lyophilization or in vacuo evaporation followed in order to store siderophores. Siderophore structure was determined using liquid chromatography and tandem mass spectrometry (LC/MS/MS) with fatty acid methyl ester (FAME) analysis. Vesicle self-assembly studies were performed using dynamic light scattering (DLS) and epifluorescence microscopy (employing cryoembedding and cryosectioning). Three new amphiphilic siderophore families (two from SL01 and one from SL28) were produced by the bacterial isolates, found to be most closely related to Halomonas variablis and Halomonas pantelleriensis, respectively. These siderophores resemble the amphiphilic aquachelin siderophores produced by Halomonas aquamarina strain DS40M3, a marine bacterium. Addition of ferric iron (Fe⁺³) at different equivalents demonstrated vesicle formation and this was confirmed by both DLS and epifluorescence microscopy. Bacteria thriving under saline and alkaline conditions are capable of producing unique siderophores resembling those produced by microbes inhabiting marine environments. Vesicle self-assembly was confirmed quantitatively and qualitatively. Amphiphilic siderophores may have different applications in medical and environmental fields.

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Coklin, Tatjana. "Detection and molecular characterization of Giardia and Cryptosporidium in Canadian dairy cattle." Thesis, University of Ottawa (Canada), 2007. http://hdl.handle.net/10393/27823.

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Giardia and Cryptosporidium are intestinal protozoan parasites that infect a wide range of host species, including humans. DNA sequencing of Giardia and Cryptosporidium isolates from human and animal sources has identified numerous species and genotypes, and has demonstrated that a number of Giardia and Cryptosporidium genotypes are shared between animals and humans. Therefore, livestock may act as a source of contamination of the food and water supply. The goal of this study was to optimize methods for the detection and molecular characterization of Giardia and Cryptosporidium. Achieving this objective involved the incorporation of immunomagnetic separation, as well as the evaluation of different methods, including microscopy, flow cytometry and polymerase chain reaction. A number of faecal samples from adult cattle and calves were collected from farms in Ontario and Prince Edward Island (PEI). Following DNA extractions from stool samples, a nested-PCR was used for Giardia to amplify a fragment of the 18S rRNA gene generating a 292-bp product. Nested-PCR protocol was also used for Cryptosporidium to amplify fragments of the heat-shock protein 70 (HSP-70) gene (ca. 325 bp). For Giardia, of 143 cattle samples analyzed by PCR, 32 (22.4 %) were positive. When IMS was incorporated into the methodology, 64 out of 143 (44.8 %) samples analyzed were positive for Giardia. For Cryptosporidum, out of 143 cattle faecal samples analyzed by the PCR method using the HSP-70 gene, 58 were positive (40.6 %), while using IMS, plus PCR, 60 samples were positive (42 %). Results from this study indicated that incorporation of IMS significantly improve the sensitivity of PCR for the detection of both Giardia (p<0.01) and Cryptosporidium (p=0.02). Among the other genes that were targeted, including the beta-giardin gene and glutamate dehydrogenase (GDH) for Giardia, and the Cryptosporidium oocyst wall protein (COWP) and 18S rRNA for Cryptosporidium, the 18S rRNA for Giardia , and HSP-70 for Cryptosporidium were found to be the "best genes". When different methods, including microscopy, flow cytometry and PCR-IMS were compared, the PCR method showed the highest sensitivity in detecting both parasites. Genotyping done by DNA sequencing showed that there was a high prevalence of zoonotic genotypes (Assemblage A for Giardia , and C. parvum bovine genotype for Cryptosporidium ) among the samples from both PEI and Ontario. In addition, a temporal study was done on calf samples from Ontario and showed that over time there was a decrease in Cryptosporidium infections, concomitant with an increase in Giardia infections.

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Paula, Ana Maria Ramalho de. "Detecção de Salmonella em alimentos crus de origem animal empregando os imunoensaios rápidos TECRATM Salmonella VIA, TECRATM Salmonella UNIQUE e o método convencional de cultura." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-08072009-160822/.

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A presença de Salmonella em 200 amostras de alimentos crus de origem animal foi investigada empregando-se os dois ensaios imunoenzimáticos rápidos TECRA™ Salmonella VIA e TECRA™ Salmonella UNIQUE (TECRA Diagnostics, Rosewille, NSW, Australia) e o método de cultura convencional empregado rotineiramente no Instituto Adolfo Lutz, São Paulo, SP. Quarenta e cinco amostras (22.5%) foram Salmonella positivas por pelo menos um dos três métodos. O número de amostras positivas de acordo com o método analítico foi 34 (75,6%) para o método de cultura convencional, 29 (64,4%) para TECRA™ Salmonella VIA e 27 (60.0%) para TECRA™ Salmonella UNIQUE. O método de cultura convencional detectou quatro amostras positivas não detectadas por nenhum dos outros dois métodos rápidos. TECRA™ Salmonella UNIQUE detectou sete amostras positivas não detectadas pelos demais métodos. Uma amostra foi positiva apenas pelo método TECRA™ Salmonella VIA. Considerando todos os resultados (positivos e negativos) o teste de qui quadrado de McNemar indicou que as diferenças entre os resultados obtidos pelos métodos rápidos, quando comparados aos obtidos pelo método convencional, não foram estatisticamente significativas (p>0.05).
The presence of Salmonella in 200 raw food samples of animal origin was investigated by means of rapid immunoassays TECRA™ Salmonella VIA and TECRA™ Salmonella UNIQUE (TECRA Diagnostics, Rosewille, NSW, Australia) and the cultural procedure used routinely in Instituto Adolfo Lutz, Sao Paulo, SP. Forty-five samples (22.5%) were Salmonella positive by at least one of the three methods. The number of positive samples according to the analytical method was 34 (75.6%) for the cultural procedure, 29 (64.4%) for TECRA™ Salmonella VIA and 27 (60.0%) for TECRA™ Salmonella UNIQUE. The cultural method detected four positive samples that both rapid methods were unable to detect. TECRA™ Salmonella UNIQUE detected seven positive samples that were not detected by the two other methods. One sample was positive by the TECRA™ Salmonella VIA exclusively. Considering overall results (positive and negative) McNemar\'s chi square tests indicated that the differences between results given by the rapid immunoassays when compared to those of the cultural method were not significant (p>0.05).

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McHale, Leah, Tasha K. Nelson, Sean Fox, and William Clark. "A Novel Compound to Combat Invasive Staphylococcal Species in Human and Animal Medicine." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/asrf/2019/schedule/177.

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An alarming problem has plagued both human and veterinary healthcare for decades: the ever-increasing presence of antibiotic resistant bacteria. Specifically, Methicillin-resistant Staphylococcus aureus (MRSA) and Methicillin-resistant Staphylococcus pseudintermedius (MRSP) are of great concern. A new compound, aptly named, LavenGel has recently been developed and demonstrates treatment potential to effectively inhibit the growth of at least two Staphylococcus species: S. aureus and S. pseudintermedius. LavenGel has been previously shown in our lab to inhibit a variety of microbes, particularly S. aureus. However, the molecular pathway that LavenGel utilizes to inhibit S. aureus and whether this inhibition could be translated to other Staphylococcus species, particularly in animals, has yet to be investigated. The major aims of this study are to demonstrate and quantify the efficacy of LavenGel in preventing S. aureus and S. pseudintermedius growth and to understand the specific S. aureus cellular mechanisms that LavenGel impacts. In order to quantitatively represent the effectiveness of LavenGel for veterinary purposes, biofilms of S. pseudintermedius were treated at different phases of development. LavenGel inhibited both the attachment of cells to form biofilms, as well as the eradication of pre-existing biofilms. Minimum inhibitory concentrations and minimum bacterial concentrations were determind for S. pseudintermedius. To better understand the impact that LavenGel may have in human healthcare, a panel of genes expressed under LavenGel treatment were examined. LavenGel does not induce the typical SOS response in S. aureus that is seen when using other leading bactericidal treatments for Staphylococcus infections which have also been shown to induce resistance. LavenGel could potentially help solve the bacterial resistance issue by working against the bacterial cell membrane instead of inducing the typical SOS response. The threat of antibiotic resistant bacteria is a constant concern in the scientific and healthcare community. The implications of this study dictate LavenGel is a highly effective, all-natural, unique option for treating common Staphylococcus infections in both veterinary and human healthcare and shows promise as a treatment that, as of yet, does not induce bacterial resistance. LavenGel could prove to be a powerful tool in the future of medical management of bacterial infections.

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Murta, Aline Ribeiro. "Perfil epidemiológico e análise microbiológica de infecção de sítio cirúrgico em pacientes humano e animal de companhia." Universidade Federal de Viçosa, 2013. http://locus.ufv.br/handle/123456789/5158.

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Made available in DSpace on 2015-03-26T13:47:18Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1129609 bytes, checksum: a3efeca5c3602073a6372b6303d99ce6 (MD5) Previous issue date: 2013-07-31
Surgical site infection (SSI) has been indicated as the third cause of nosocomial infection. The present study aimed at determining the epidemiological profile of SSI and its association to the described risk factors. It is a transversal study done at the São João Batista Hospital at at Viçosa-MG and at the Surgery Service of the Small Animals Veterinary Hospital of the Universidade Federal de Viçosa-MG, from September 2012 to February 2013. SSI global rates were 0.7% at the human and 3.46% at the veterinary hospitals. At the veterinary hospital, SSI rates were not related to contamination potential, with clean procedures presenting the greater rates. As for the type of surgery, orthopedic ones are the most common in both hospital and also the ones presenting the greater SSI rates. The diagnosis of SSI occurred within 30 days after surgery, and data HVT-UFV demonstrated effectiveness studies developed in this hospital, indicating improvement in the prevention and control of SSI, but in both hospitals is not performed surveillance post-discharge of patients, and may infer that there was underreporting of SSI. Bacteria isolated from surgical wounds were multi-resistant and the obtained data indicated that no criteria of antibiotic prophylaxis existed, mainly for clean surgeries. This scenario shows that the action of a commission to control nosocomial infection are extremely relevant in order to guarantee reliable data so that the quality of service may be evaluated and thus, promoting a decrease the risk of in post-operative complications.
A infecção de sítio cirúrgico (ISC) tem sido apontada como a terceira causa mais comum de infecção nosocomial. Este estudo objetivou determinar o perfil epidemiológico das ISCs e sua associação aos fatores de risco descritos. Trata-se de um estudo transversal, realizado no Hospital São João Batista de Viçosa-MG e na Clínica Cirúrgica de Cães e Gatos do Hospital Veterinário da Universidade Federal de Viçosa- MG, no período de setembro de 2012 a fevereiro de 2013. As taxas globais de ISC foram de 0,7% no hospital humano e 3,46% no veterinário. No hospital veterinário, a taxa de ISC não mostrou relação com o potencial de contaminação, apresentando a maior taxa nos procedimentos classificados como limpos. Quanto ao tipo de cirurgia, as ortopédicas são as mais comuns em ambos os hospitais e também as que apresentam maior taxa de ISC. Foi observada diferença significativa nas cirurgias com duração superior a 40 minutos pelos testes não paramétricos de Wilcoxon e Mann-Whitney (p=0,041) no HVT-UFV. O diagnóstico das ISC ocorreu dentro dos 30 dias após a cirurgia, e dados do HVT-UFV demonstraram efetividade dos estudos desenvolvidos neste hospital, indicando melhora das medidas de prevenção e controle das ISC, porém em ambos os hospitais não é realizada a vigilância pós-alta dos pacientes, podendo inferir que houve subnotificação das ISC. As bactérias isoladas das feridas cirúrgicas foram multirresistentes e os dados levantados indicam que não houve critério quanto ao emprego da antibioticoprofilaxia, principalmente nas cirurgias limpas. Este cenário mostra que é de extrema relevância a atuação de uma comissão de controle de infecção hospitalar, a fim de garantir obtenção de dados fidedignos, para que se possa avaliar a qualidade do serviço prestado e assim promover a redução dos riscos de complicações pós-operatórias.

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Mendonça, Daiane Barros Dias. "Análise do microbioma de bactérias de luz intestinal de hamsteres e sua correlação com LPS circulante, decorrente da translocação microbiana na leishmaniose visceral experimental." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/99/99131/tde-22012018-114555/.

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A leishmaniose visceral, na sua forma clinica ativa, caracteriza-se por febre de longa duração, hepatoesplenomegalia e caquexia. No Brasil, a letalidade é, em média, de 7% e as principais causas de morte são: hemorragia, comorbidade com doenças imunossupressoras e infecção bacteriana. O mecanismo de aumento de infecção bacteriana na LV não está claro e uma das hipóteses, é que pode haver translocação bacteriana da mucosa intestinal para o lúmen dos vasos sanguíneos e ocasionar uma maior severidade da resposta imuno-inflamatória e com consequente piora clínica. O objetivo deste trabalho foi avaliar a ocorrência de translocação microbiana em hamsteres infectados experimentalmente com Leishmania (L.) infantum e correlacionar com as alterações histopatológicas encontradas no intestino dos animais infectados. Hamsteres (Mesocricetus auratus) foram infectados intraperitonealmente com 2x107 amastigotas de L. (L.) infantum e eutanasiados após 48, 72 horas e 15, 45 e 90 dias de infecção. Como grupo controle foram utilizados hamsteres inoculados intraperitonealmente com meio de cultura RPMI. Foram coletados: sangue, fezes, baço, intestinos grosso e delgado. Para detecção de amastigotas na mucosa intestinal, foi utilizada a técnica de PCR em tempo real (qPCR), imunohistoquímica e análise histopatológica, sendo que nesta técnica também foram avaliadas alterações histológicas no tecido intestinal. O baço foi utilizado para determinar a carga parasitária através da técnica de Stauber. Para detecção da translocação microbiana ou produtos desde, foi realizada a quantificação de lipopolissacarídeo (LPS) em plasma. Para avaliar a possível mudança da flora bacteriana intestinal, foi realizado sequenciamento bacteriano de amostra de fezes de hamsteres controles e infectados nos vários tempos de infecção. Observamos aumento da carga parasitária em baço e em intestino com o decorrer da infecção, sendo a diferença significativa aos 90 dias de infecção. Paralelamente, observamos aumento de LPS circulante nos animais infectados em diferentes tempos, 48 horas, 72 horas, 45 dias e 90 dias, com diminuição no período intermediário de 15 dias, porém com diferença significante somente aos 90 dias após a infecção em relação ao grupo controle. Alterações histopatológicas foram observadas no intestino grosso e delgado, variando de infiltrado inflamatório leve a grave, enterite, histiocitose e ainda presença de amastigotas. As alterações observadas ocorreram a partir de 48 horas de infecção, diferenciando a população do infiltrado inflamatório entre neutrófilos, linfócitos, e ainda eosinófilos em intestino grosso de animais com 90 dias de infecção. O sequenciamento de DNA bacteriano das fezes mostra que houve alteração no microbioma dos animais, porém não há identidade significante, ou seja, acima de 95% na maioria das bactérias. Concluímos que as alterações de histologia da mucosa, a invasão de amastigotas neste tecido e o aumento do LPS, sugerem que a translocação microbiana é um evento ocorrente durante a infecção por L. (L.) infantum neste modelo experimental.
Visceral leishmaniasis, in its active clinical form, is characterized by long-lasting fever, hepatosplenomegaly and cachexia. In Brazil, the lethality is, on average, 7% and the main causes of death are hemorrhage, comorbidity with immunosuppressive diseases and bacterial infection. The mechanism of increased bacterial infection in LV is unclear and one of the hypotheses is that there may be bacterial translocation of the intestinal mucosa to the lumen of the blood vessels and cause a greater severity of the immune-inflammatory response and consequent clinical worsening. The objective of this work was evaluate the occurrence of microbial translocation in Leishmania (L.) infantum infected-hamsters and correlate with the histopathological changes found in the gut of infected animals. Hamsters (Mesocricetus auratus) were infected intraperitoneally with 2x107 amastigotes of L. (L.) infantum and euthanized after 48, 72 hours and 15, 45 and 90 days of infection. As a control group, hamsters were inoculated intraperitoneally with RPMI culture medium. Were collected: blood, feces, spleen, large and small intestines. To detection amastigotes in intestinal mucosa, real-time PCR (qPCR), immunohistochemistry and histopathological analysis were used, and histological alterations in intestinal tissue were also evaluated. Spleen was used to determine the parasitic load through the Stauber technique. To detection of microbial translocation or products related, was performed quantification of lipopolysaccharide (LPS) in plasma. In order to evaluate the possible change in intestinal bacterial flora, bacterial sequencing of sample faeces from control and infected hamsters was carried. We observed increased parasite load on spleen and intestine as the infection progressed, the difference being significant at 90 days of infection. At the same time, we observed increased circulating LPS in infected animals at different times, 48 hours, 72 hours, 45 days and 90 days, with decrease in the intermediate period of 15 days, howeversignificant difference was observed only at 90 days post-infection in relation to control group. Histopathological changes were observed in the large and small intestine, ranging from mild to severe inflammatory infiltrate, enteritis, histiocytosis, and amastigotes. The changes occurred from 48 hours of infection, differentiating the population of the inflammatory infiltrate between neutrophils, lymphocytes, and even eosinophils in the large intestine of animals with 90 days of infection. |Bacterial sequencing shows that there was a change in the microbiome of the animals, but there is no significant identity, ie, above 95% in most bacteria. We conclude that changes in mucosal histology, invasion of amastigotes in this tissue and increase in LPS, suggest that microbial translocation is an event occurring during L. (L.) infantum infection in this experimental model.

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Nascimento, Diana Costa. "Ocorrência de leveduras pertencentes ao gênero Cryptococcus em cloaca e inglúvio de papagaios do gênero Amazona aestiva." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/42/42132/tde-07102013-103027/.

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Realizamos o isolamento de leveduras do complexo Cryptococcus a partir da cloaca e do inglúvio de papagaios do gênero Amazona aestiva. Para a realização das coletas, as aves foram anestesiadas, e em seguida foi realizado lavado do inglúvio e coleta de material da cloaca. As amostras coletadas foram inoculadas em ágar Sabouraud dextrose com cloranfenicol, de onde foram isoladas colônias leveduriformes. Por meio de análises macro e micromorfológicas, os isolados condizentes com as características do gênero Cryptococcus foram submetidos à provas bioquímicas, testes de suscetibilidade aos antifúngicos e pesquisa de exoenzimas. Todos os isolados foram provenientes da cloaca. Dos isolamentos, 90% das cepas corresponderam à espécie C. albidus, e 10% à espécie C. laurentii; 80% foram produtores de fosfolipase e 100% de proteinase. Estes resultados sugerem que não só o ambiente, como também as aves podem ser carreadoras de Cryptococcus albidus.
We performed the isolation of yeasts of Cryptococcus complex from the cloaca and the crop of parrots of the genus Amazona aestiva. To carry out the sampling, the birds were anesthetized to perform a lavage of the crop and the collection of material from the cloaca. The samples were inoculated on Sabouraud dextrose agar with chloramphenicol, which were isolated from yeast colonies. Through macro and micromorphological analysis, isolates consistent with the characteristics of the genus Cryptococcus were subjected to biochemical tests, antifungal susceptibility testing and research exoenzymes. All isolates were from the cloaca. Of the isolates, 90% of the strains corresponded to the species C. albidus, and 10% of the species C. laurentii; 80% of the isolates were producing phospholipase and 100% were producing proteinase. These results suggest that not only environmental but also birds can be Cryptococcus albidus carrier. These results suggest that there is not only an environmental source but also birds can be Cryptococcus albidus carriers

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Witcomb, Luci. "The in situ analysis of the microbial community associated with footrot of sheep." Thesis, University of Warwick, 2012. http://wrap.warwick.ac.uk/50463/.

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Footrot (FR) is a highly infectious and debilitating disease of sheep, which has a significant economic impact on the sheep farming industry, in the UK and worldwide and causes significant suffering of sheep. Despite some recent advances, FR remains a scientifically challenging disease to understand. To help improve our understanding of disease pathogenesis, two culture-independent techniques were developed to examine the microbial succession events between the causative agent, Dichelobacter nodosus and an accessory agent, Fusobacterium necrophorum, the latter also postulated to be involved in disease initiation. The two populations were monitored in relation to disease initiation and progression during a longitudinal study and disease presentation in tissue biopsies (in situ). Finally, the distribution of these two species of bacteria in the environment was examined to highlight possible sources of infection. The work in this thesis has demonstrated that FR is a disease where expression is related to D. nodosus load present in the ovine interdigital space. D. nodosus (rpoD) load increased from that on a healthy foot to one presenting with interdigital dermatitis (ID) and feet with a higher D. nodosus (rpoD) load were more likely to go on to develop FR one week later. FISH analysis of the D. nodosus population present within the epidermis also revealed similar findings; D. nodosus cell counts increased during stages of ID, but the organism was less frequently detected in biopsies from feet with FR. Suggesting that ID might be the most infectious stage of the disease process. A fact that needs to be highlighted to farmers to encourage treatment at this stage of disease. In contrast, F. necrophorum (rpoB) load did not correlate with ID presentation or prior to the development of FR, but increased the week of FR onset. FISH analysis also revealed that F. necrophorum cell counts were higher in feet with FR than those with ID. It is possible therefore that F. necrophorum may thrive in the altered environment of a foot presenting with FR, possibly contributing to disease persistence and severity. Finally, both pathogens were detected in a range of environmental samples from a farm with endemic FR, highlighting possible sources of infection and material, which once contaminated with D. nodosus and F. necrophorum may contribute to the spread of FR. This study has provided an improved understanding of the microbial population dynamics involved in the development of ID and FR in sheep, which may have implications for control and treatment practices not only in the UK, but world-wide.

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Latham, Sopia Maria. "The epidemiology of Neospora caninum." Thesis, University of Glasgow, 2003. http://theses.gla.ac.uk/4239/.

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A seroepidemiological study was undertaken in a pedigree dairy herd that had a history of abortions due to neosporosis. The infection in this closed herd was thought to have arisen from a point-source infection, after which sporadic abortions have occurred. All cattle were bled twice, once in the winter and again the following summer and antibodies to N. caninum measured using an ELISA. The overall seroprevalence of Neospora was found to be 18 %. Three data sets; age-prevalence data, dam-daughter pair analysis and family tree data showed vertical transmission to be an important route of transmission of neosporosis in this herd. Analysis of anti- Neospora antibody titres with respect to the stage in the breeding cycle of cows appeared to show no association on a herd level. Data was collected on the number of Artificial Insemination (AI) services per successful pregnancy which showed a significantly greater number of Al services in Neospora-seropositive cattle compared with Neospora-seronegative cattle. This is the first study to assess the effect of neosporosis on cattle fertility in a quantitative manner and suggests that a wider study is justified. N. caninum shares many similarities with T gondii and has widely been assumed also to have a world-wide distribution. Two regions of Africa, Ghana in West Africa and Tanzania in East Africa, were studied in a cross-sectional survey of neosporosis in cattle indigenous to these areas. A prevalence of 8.1 % and 2% was found in two different areas in cattle native to Tanzania. Despite sampling a significant number of cattle in all three ecological zones of Ghana and of several different breeds, no Neospora-seropositive cattle were found. Possible reasons for the apparent absence of N. caninum in West Africa are discussed. To determine the overall genetic diversity in laboratory isolates of N. caninum, RAPD and AFLP methods were used. Genetic diversity was found to be low amongst Neospora laboratory isolates, relative to T. gondii, but demonstrated that genetic heterogeneity does exist within the species. Both RAPD and AFLP data were subjected to pair-wise similarity and cluster analysis and showed that there was no clustering with respect to host or geographical origin. The genetic similarity between cattle and dog isolates suggests that these hosts are epidemiologically related. In order to exploit the genetic heterogeneity in N. caninum to analyse a wider range of clinical field samples, several methods were attempted to devise PCR-based sequence-specific typing approaches that could be used on infected bovine tissue. Microsatellite markers were identified in N. caninum DNA sequences, however none of the microsatellite regions gave rise to detectable size differences, although they remain to be tested on a wider range of field samples. Laboratory isolates of N. caninum were also analysed for polymorphisms with two conserved minisatellite probes, 33.6 and 33.15, but although hybridisation occurred to digested parasite DNA, identical fingerprints were obtained for each isolate. In a final attempt to identify sequence-specific polymorphic markers, intron regions from two genes, actin and tubulin, were amplified and sequenced in both laboratory and field isolates. This approach revealed a number of single nucleotide polymorphisms (SNPs) that were able to differentiate between some isolates of N. caninum and might serve as useful molecular markers. SNPs were found more frequently in the clinical field samples, suggesting that the diversity of N. caninum is greater than that represented by current laboratory isolates. Further genotyping of field samples will enable the genetic population structure of N. caninum to be determined to facilitate molecular epidemiological studies.

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24

Silistre, Hazel. "Riboregulation in Pseudomonas aeruginosa." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/32634/.

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The opportunistic human pathogen Pseudomonas aeruginosa controls virulence, production of secondary metabolites, motility, biofilm formation, growth in anaerobic conditions, intracellular and intercellular signalling and the switch from an acute to a chronic mode of infection at the transcriptional and post-transcriptional levels by modulation of the Gac/Rsm system. Cell density-dependent signal accumulation and environmental stimulators such as pH changes and ion limitation activate the GacS/GacA two-component system which in turn triggers transcription of the small regulatory RNAs RsmY and RsmZ. These sRNAs sequester multiple copies of the RNA-binding protein RsmA, antagonising its function. The RsmA/CsrA proteins act as translational repressors by binding to the GGA-motifs in the untranslated region of target mRNAs and blocking ribosome binding. In this study, the biological function of RsmN, an RsmA homologue with a conserved RNA-binding pocket but a distinct protein folding, the predicted autoregulatory mechanism of RsmN, the nature of target transcripts of RsmN, and the cross-regulation between the two Rsm proteins were investigated. The positive control of proteolytic and elastinolytic activities and swarming motility by RsmN has been demonstrated using single and inducible double deletion mutants of rsmN. Furthermore, rsmN deletion increased microcolony formation during biofilm formation. Regulation by RsmN was most apparent in the absence of RsmA, when rsmN expression was induced via a multicopy plasmid and at temperatures lower than 37°C. The double deletion of rsmA and rsmN affected growth, diminished proteolytic and elastinolytic activities, triggered autolysis and led to the increased secretion of the type VI secretion system protein Hcp1. Moreover, the double deletion of rsmA and rsmN altered the colony morphology of P. aeruginosa. Mutagenesis of the functionally critical, conserved RNA-binding residue which is identified as Arg44 in RsmA and Arg62 in RsmN resulted in the loss of RsmN function. In a genome-wide analysis by RNASeq, target transcripts were co-purified with RsmN from 37°C and 34°C cultures of a wild-type strain expressing rsmN in multicopy numbers. RNASeq results indicated that small regulatory RNAs such as CrcZ, RsmY and RgsA are common targets of RsmN and RsmA, whereas PhrS is a target of RsmN only. Other common RsmA and RsmN targets included transcriptional regulators, heat shock proteins, proteases, starvation response proteins, components of the denitrification pathway, outer membrane proteins required for pore formation, type III and type VI secretion system proteins and RsmA. Transcripts of heat shock proteins, the tss operon genes and rsmA were enriched by RsmN at 37°C but not at 34°C whereas the lasB transcript was enriched by RsmN at 34°C but not at 37°C. Based on the list of common targets of RsmA and RsmN and the results obtained from phenotypic assays, induction of the lytic Pf4 prophage, accumulation of alkyl quinolone or c-di-GMP signalling molecules, imbalanced redox state, carbon starvation, increased membrane permeability, and aggregation of misfolded proteins are suggested as possible mechanisms triggering the excessive autolysis of the rsmNind ΔrsmA mutant under uninducing conditions. The data gathered so far suggests that rsmN is differentially expressed, with increased RsmN activity at temperatures below 37°C in comparison with RsmA, and, RsmA and RsmN collectively contribute to the regulation of secondary metabolite production, motility and microcolony formation in P. aeruginosa.

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Hamidou, Soumana Illiassou. "La Trypanosomose Humaine Africaine (maladie du sommeil) : caractérisation de gènes impliqués dans les interactions symbiontes - glossines - trypanosomes." Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20182.

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Les glossines (mouches tsétsé) sont les vecteurs des trypanosomes africains, responsables de la Trypanosomose Humaine Africaine (THA) ou maladie du sommeil en Afrique sub-saharienne. De nouvelles stratégies de lutte contre la THA visent à utiliser les symbiontes de la glossine pour augmenter sa réfraction à l'infection par les trypanosomes. La mise en place de telles approches nécessite une bonne connaissance des bases moléculaires et cellulaires des interactions entre les symbiontes, la glossine et le trypanosome. Les objectifs de cette thèse étaient, i) d'évaluer l'évolution des densités des symbiontes (Wigglesworthia glossinidia et Sodalis glossinidius) au cours du cycle de développement du vecteur et ii) de caractériser les gènes de Sodalis, Glossina palpalis gambiensis et Trypanosome brucei gambiense en interaction et qui s'expriment différentiellement au cours de l'infection. Nous avons pu montrer la présence permanente des deux symbiontes quel que soit le stade de développement de la glossine, ce qui permet leur utilisation dans le cadre du contrôle des vecteurs. Par la suite, des infections expérimentales ont été réalisées sur des glossines d'insectarium. Des glossines de l'espèce G. p. gambiensis ont été gorgées sur des souris infectées par T. b. gambiense. L'analyse des métatranscriptomes des glossines infectées versus réfractaires à l'infection nous ont permis de mettre en évidence les gènes de Sodalis, G. p. gambiensis et T. b. gambiense différentiellement exprimés aux étapes clé de l'infection. Les résultats qui découlent de cette thèse mettent la lumière sur la complexité des interactions Sodalis - G. p. gambiensis - T. b. gambiense et soulignent l'implication des bactériophages du symbionte S. glossinidius dans la réfraction des glossines à l'infection. Mots clés : maladie du sommeil, mouche tsétsé, trypanosome, symbiontes, compétence vectorielle, expression de gènes
Tsetse flies are the vectors of African trypanosomes, the causative agents of human African trypanosomiasis (sleeping sickness)in sub-saharan Africa. New sleeping sickness control strategies plan to use tsetse gut symbionts to increase tsetse flies refractoriness to trypanosomes infection. Such approaches require good knowledge on the molecular and cellular basis of interactions between symbionts, tsetse fly and trypanosome. This thesis aimed to i) assess the evolution of Glossina palpalis gambiensis symbionts (Wigglesworthia glossinidia and Sodalis glossinidius) densities throughout the host fly development cycle and ii) to characterize genes of Sodalis, G. p. gambiensis and Trypanosoma brucei gambiense in interaction, which are differentially expressed during the infection. We showed that both symbionts are present in all tsetse fly development stages, allowing their use in the context of vector control. Subsequently, experimental infections were performed on colonies flies. G. p. gambiensis female flies were fed on T. b. gambiense hosting mice. Transcriptome of infected flies and flies that have cleared trypanosome they ingested were analysed. This allow us identifying genes of Sodalis, G. p. gambiensis and T. b. gambiense differentially expressed at the infection key stages. Our results highlight the complexity of interactions between Sodalis, G. p. gambiensis, T. b. gambiense and underline the involvement of bacteriophages hosted by S. glossinidius in tsetse fly refractoriness to trypanosome infection. Key words: sleeping sickness; tsetse fly; trypanosome; symbionts; vector competence; gene expression

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26

Cardozo, Marita Vedovelli. "Salmonella spp. e Clostridium perfringens em farinhas de origem animal utilizadas na fabricação de rações e avaliação de aditivo na inibição de patógeno /." Jaboticabal : [s.n.], 2011. http://hdl.handle.net/11449/94934.

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Orientador: Ruben Pablo Schocken Iturrino
Banca: Oswaldo Durival Rossi Junior
Banca: Alessandra Aparecida Medeiros
Resumo: O processamento dos resíduos gerados durante a produção avícola origina subprodutos que podem ser utilizados na alimentação animal resultando em rações economicamente viáveis. Entretanto, a qualidade dos ingredientes que compõem a ração é de extrema importância, pois o alimento pode veicular diversos patógenos. Dessa forma foi desenvolvido o presente estudo, com o objetivo de avaliar através dos métodos bacteriológicos convencionais a qualidade microbiológica de Farinha de Vísceras (FV), Farinha de Sangue e Penas (FSP) e Farinhas de Carne e Ossos (FCO) no que se refere a contaminação pelos microrganismos Salmonella spp. e Clostridium perfringens, bem como testar a eficiência para inibição microbiana de um produto químico a base de formaldeído e ácidos orgânicos. Das 180 amostras de farinhas analisadas, 71 (39,4%) apresentaram resultado positivo em relação à presença de C. perfringens, e 41 (22,8%) apresentaram resultado positivo quanto à presença de Salmonella spp. O produto a base de formaldeído e ácidos orgânicos mostrou-se eficiente na inibição de C. perfringens pois as contagens diminuíram significativamente após 24 horas e, após cinco dias foi observado ausência total do microrganismo nas amostras testadas. A presença dos patógenos Salmonella spp. e C. perfringens em todos os tipos de farinhas analisadas evidencia que este sub-setor necessita de aportes tecnológicos, além de serem responsáveis por perdas econômicas aos produtores e um risco à saúde pública. A eficiência do produto químico testado mostra que existe forma de inibir o crescimento do C. perfringens, um grande avanço para a avicultura
Abstract: The processing of the waste generated during production originates poultry products that can be used in animal feed rations resulting in economically viable. However, the quality of the ingredients in the diet is extremely important, because the food may carry various pathogens. Thus the present study was developed with the aim to assess by conventional bacteriological methods the microbiological quality of poultry offal meal (POM), Blood Meal and Feather (FSP) and Meat and Bone meal (MBM) with regard to contamination by pathogens Salmonella spp. and C. perfringens, as well as testing the efficiency of the chemical basis of formaldehyde and organic acids. Of 180 flour samples analyzed, 71 (39.4%) were positive for the presence of Clostridium perfringens, and 41 (22.8%) were positive for the presence of Salmonella spp. The base product of formaldehyde and organic acids proved effective in inhibiting C. perfringens as the counts decreased significantly after 24 hours, and after five days was observed total absence of the microorganism in the samples tested. The presence of the pathogens Salmonella spp. e C. perfringens in all kinds of flours analyzed shows that this sub-sector needs technological contributions, besides being responsible for economic losses to producers and a public health risk. The efficiency of the chemical test shows that there is no way to inhibit the growth of C. perfringens, a major breakthrough for the poultry industry
Mestre

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27

Wong, Andrew Hoi-Tao 1974. "Interdependence of the double-stranded RNA-activated protein kinase, PKR, and the transcription factor, STAT1, in intgerferon signalin and translatioinal control." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36850.

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Interferons (IFNs) are polypeptides that protect the body from microbial infection by the activation of genes that inhibit the replication of such pathogens. STAT1 is a transcription factor that is activated by IFNs and virus infection, and propagates signals to the nucleus by binding DNA enhancer elements to induce the expression of IFN-stimulated genes (ISGs). One such gene product is the double-stranded RNA (dsRNA)dependent protein kinase, PKR. PKR is an important determinant of host resistance since it has the ability to bind dsRNA, an intermediate produced during viral replication, and to phosphorylate the eukaryotic translation initiation factor-2alpha (eIF-2alpha), a modification that inhibits of protein synthesis. Additionally, recent findings have shown that PKR can modulate various signaling pathways. The objective of this research was to understand the involvement of PKR in the IFN signaling pathways. We observed that the catalytic domain of PKR interacts with the DNA-binding region of STAT1 in vitro and in vivo. Overexpression of catalytic mutants of PKR blocked STAT1 DNA-binding and ISG expression upon IFN or dsRNA treatment. The capacity of catalytic mutants of PKR to negatively regulate STAT1 DNA-binding is attributed to its ability to interact with STAT1 since in cells lacking PKR or expressing an RNA-binding mutant of PKR, unable to associate with STAT1, STAT1 displays augmented activity. A mutant of STAT1 (TM) unable to interact with PKR displayed elevated biochemical and biological activities; findings consistent with the role of PKR in regulating STAT1 function. Alternatively, the interaction between PKR and STAT1 has the ability to inhibit PKR activity in vitro and in vivo; a phenomenon not observed with STAT1 TM.
In parallel, PKR was also found to interact with TYK2, the upstream activator of STAT1. IFN treatment promoted the dissociation of PKR from TYK2 in a manner dependent on TYK2 kinase activity. Furthermore, we observed that TYK2 phosphorylates the amino terminus of PKR in vitro and in vivo on tyrosine. Taken together, PKR appears to function as an important scaffolding protein for the IFN signaling pathways. Alternatively, PKR activity itself is also regulated at multiple steps along this pathway. Thus, it appears that there is an intimate cross-talk between components of the JAK/STAT pathway and translational machinery.

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28

Rosales, Mauricio. "In vitro assessment of the nutritive value of mixtures of leaves from tropical fodder trees." Thesis, University of Oxford, 1996. http://ora.ox.ac.uk/objects/uuid:cb8e7b8f-fabb-4aed-a5c5-8a58b6c294a6.

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Previous work in animal nutrition has focused on single feeds and assumed additivity in ration systems. In the tropics, farmers are likely to feed mixtures of feeds, including tree fodders, which may not be simply additive in nutritional terms. This study has increased our understanding of the mechanisms that determine the associative effects on the in vitro fermentation of mixtures of fodder tree leaves. Associative effects are governed by a synchronisation in the fermentation rates of the components of the mixture. This is in turn dependent on the fermentability of their chemical constituents. Effects were demonstrated by changes in the fermentation kinetics of gas production curves. The chemical components of fodder tree leaves that affect the fermentation, and the time at which the effect occurs, were identified, using two media of different nitrogen contents. The fermentation of mixtures of pure chemical entities in various combinations was then examined. The greatest associative effects were found when the mixture had components of similar fermentability. It is proposed that associative effects are a function of the synchronisation of fermentation of the different components and was shown to occur at the point when the rate was maximal. With two types of protein (casein and bovine serum albumin (BSA)), utilisation of a protein by rumen microbes was shown to be a function of its fermentability and not of its solubility. This is also influenced by the type of associated carbohydrate. Fodder tree leaves were then combined with different pure chemical entities. Associative effects between fodder tree leaves and carbohydrates were shown to occur and the responses were similar to those obtained with mixtures of pure carbohydrates and proteins. The effect of tannins and phenolic compounds was studied using quebracho tannin as a model, and in five of the tree species. They were shown to affect the fermentability of both carbohydrates and proteins. The effect was greater with carbohydrates of medium to low fermentability. They also reacted with both soluble and insoluble protein. Forages with phenolic compounds showed both positive and negative effects. The effects were possible due to a synchrony or asynchrony in the release of protein. In mixtures of leaves from different species, associative effects were related to their fermentability. Again, this appeared to be the result of the synchronisation of the release of nutrients. Associative effects with fodder tree leaves were of a composite nature and can be both positive and negative. The implications of these findings in relation to in vivo digestion and animal production are discussed. Due to the diversity of fodder trees, there is the potential to develop feeding systems based on mixtures which make better use of available resources. This will also contribute to improved efficiency in the management and use of natural resources, and take advantage of natural plant diversity in the tropics.

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29

Gauthier, David T. "Pathobiology of mycobacteria in striped bass (Morone saxatilis)." W&M ScholarWorks, 2004. https://scholarworks.wm.edu/etd/1539616661.

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Striped bass (Morone saxatilis) in Chesapeake Bay, USA, are experiencing an epizootic of mycobacteriosis. This disease, caused by bacteria in the genus Mycobacterium, causes granulomatous lesions of the skin and viscera. Diseased fish are often emaciated, and fish with skin lesions may be significantly disfigured. The overall goal of this work was to examine aspects of the pathobiology of mycobacteria in striped bass via laboratory exposure studies and cellular assays. Striped bass were injected intraperitoneally with a sublethal dose of Mycobacterium marinum, M. shottsii, or M. gordonae and sampled for histology and bacteriology at regular intervals to 45 weeks post-injection (p.i.). Fish injected with M. marinum developed granulomas in the mesenteries, spleen and anterior kidney. Acid-fast bacilli (AFB) were rare in initial stages of disease whereas granulomas at 8 weeks p.i. and later frequently contained large numbers of AFB. Secondary disease was observed in some fish between 26 and 45 weeks p.i., with granuloma disintegration, severe inflammation, and elevated splenic bacterial densities. Relative to fish injected with M. marinum, fish injected with M. shottsii or M. gordonae did not develop severe pathology. Granulomas were observed in the mesenteries, but were not observed in the spleen or, with one exception, anterior kidney. M. shottsii and M. gordonae both established persistent splenic infections. The ultrastructure of developing M. marinum granulomas in experimentally infected bass was examined. Formation of large macrophage aggregations containing intracellular bacilli was observed within the peritoneal cavity shortly after injection. M. marinum were always contained within phagosomes, and apparent phagolysosomal fusion was frequently observed. Epithelioid transformation of macrophages was observed. Ultrastructural observation of bacilli within granulomas agreed with histologic findings. The in vitro interaction between macrophages and intracellular M. marinum was examined ultrastructurally and with a quantitative bactericidal assay. Phagosomes containing M. marinum were fused at high rates by pre-labeled lysosomes. No differences in lysosomal fusion rates were observed between phagosomes containing live or heat-killed M. marinum. Intracellular M. marinum remained largely viable for the duration of the assay (72 hours). Heat-killed M marinum were resistant to lysis within phagolysosomes.

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Earnhart, Christopher G. "Dynamics of the host-parasite interaction: in vitro correlates of Crassostrea-induced modulation of Perkinsus marinus function." W&M ScholarWorks, 2004. https://scholarworks.wm.edu/etd/1539616637.

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Perkinsus marinus is an alveolate protozoan parasite of the eastern oyster (Crassostrea virginica) which is responsible for much of the decline in United States oyster populations. Perkinsus marinus can be cultured in vitro, but is rapidly attenuated in the process. Supplementation of a protein-free medium with oyster products altered proliferation, changed protease expression in the parasite extracellular products (ECP), induced morphological forms typically seen in vivo, and partially reversed parasite attenuation. Supplements derived from dissected oyster tissues were used to determine if these changes could be differentially elicited. These supplements, with the exception of adductor muscle, reduced proliferation. Whole oyster and digestive gland/gonad supplements favored palintomic, rather than binary, fission. The total ECP protease activity was generally decreased in supplemented cultures, though gill/mantle supplements may have induced proteases. A low molecular weight subset of proteases was upregulated most effectively by heart- and adductor muscle-derived supplements. Serine proteases and other ECP proteins may be virulence factors. Attempts to create antibodies to study P. marinus cells and ECP have been largely unsuccessful due to poor immune responses and crossreactivity. Ultrafiltration-concentrated P. marinus ECP were poorly immunogenic and toxic to experimental animals. Immunogenicity was not substantially affected by heat denaturation or proteolytic inhibition. Co-administration of ECP with oyster plasma caused a suppression in the anti-plasma antibody response with restriction of epitope recognition. Analysis of medium constituents revealed that a surfactant, Pluronic F-68 (PF68), was immunosuppressive. Although isolated protein antigens from the ECP remained immunosuppressive, separation of the antigens from PF68 enabled antibody production. Five monoclonal antibodies were created against ECP from unsupplemented medium and were used to study ECP function, regulation, and mechanism of storage and release. ECP are secreted by release from the cell wall and from two morphologically distinct intracellular compartments. A sandwich ELISA allowed quantification of an ECP protein with significantly reduced expression in supplemented cultures. Another antibody, which specifically bound to trophozoite and tomont walls, was used to investigate morphological and antigenic changes during thioglycollate-induced formation of prezoosporangia, and confirm supplement-induced formation of prezoosporangia. This antibody labeled P. marinus cells in fixed oyster tissue in a species-specific manner.

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Roman-Garcia, Yairanex. "Assessing Dietary Conditions Influencing the Requirements by Rumen Bacteria for Branched Chain Volatile Fatty Acids." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1557171743925883.

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32

Souto, Luís Ivan Martinhão. "Associação entre o índice de mastite em rebanhos bovinos leiteiros e a qualidade microbiológica do leite cru no Estado de São Paulo, Brasil." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-30052007-152355/.

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O objetivo deste trabalho foi verificar as possíveis correlações entre os índices de mastite e a qualidade microbiológica do leite cru, em 36 propriedades com atividade exploratória leiteira, no Estado de São Paulo, Brasil. Examinou-se 4662 quartos mamários de 1180 animais em lactação para se verificar a presença de mastite pelos Testes de Caneca de Fundo Escuro e CMT, e coletou-se uma amostra de cada quarto mamário positivo em pelo menos um dos testes para exame microbiológico. Para se avaliar a qualidade microbiológica do leite cru, coletou-se uma amostra de cada propriedade e fez-se a Contagem de microrganismos mesófilos aeróbios facultativos viáveis, Contagem de microrganismos psicrotróficos aeróbios facultativos viáveis, Contagem de microrganismos termófilos aeróbios facultativos viáveis, Contagem de Enterococcus spp., Contagem de Stapylococcus spp., Contagem de Streptococcus spp., Contagem de Corynebacterium spp., Contagem de bolores e leveduras, Número Mais Provável de coliformes totais e Número Mais Provável de coliformes fecais. Aplicou-se teste de Correlação de Pearson e Regressão Linear. Para comparação entre os índices de mastite, a melhor correlação foi entre o índice de resultados positivos ao teste CMT e os casos de mastite por causa infecciosa (r = 0,920 e R2 = 84,7%). Comparando-se o índice de mastite e a qualidade microbiológica do leite cru, o melhor resultado que apresentou correlação significativa foi entre o índice de casos de mastite por Staphylococcus spp. e a Contagem de microrganismos termófilos aeróbios facultativos viáveis (r = 0,522 e R2 = 27,3%). Pelo baixo número de análises que apresentaram resultado de Correlação significativa, notou-se que o índice mastite em rebanhos bovinos leiteiros não interfere na qualidade microbiológica do leite cru, nas condições estudadas neste experimento.
The purpose of this research was to investigate the possible correlations between the mastitis rate and raw milk microbiology quality, from 36 dairy farms, in São Paulo State, Brazil. It was investigated 4662 mammary quarters of 1180 lactant animals to examine mastitis cases using Tamis test and CMT. It was collected one sample of each positive mammary quarter in one test at least to microbiological analysis. To estimate the raw milk microbiological quality, it was colected one sample from each farm and realized one aerobic plate count of microorganisms mesophilic, aerobic plate count of microorganisms psychrotrophic, aerobic plate count of microorganisms termophilic, Enterococcus spp. plate count, Stahylococcus spp. plate count, Streptococcus spp. plate count, Corynebacterium spp. plate count, Yeast and Molds plate count, Most Probable Number of coliforms, Most Probable Number of fecal coliforms. It was used Pearson Correlation test and Linear Regression. In order to compare mastitis rates, the best correlation was between positives CMT test rate and the cases of mastitis caused by infections disease (r = 0,920 and R2 = 84,7%). Analysing the mastitis rate and the raw milk microbiological quality, the best result of correlation was between Staphylococcus mastitis rate and the aerobic plate count of microorganisms termophilic (r = 0,522 e R2 = 27,3%). Because of the low number of significant correlation, it was observed that the mastitis heard in dairy bovines herds do not interfere in raw milk microbiological quality, in the condition of this experiment.

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Santos, José Rodolfo dos. "Probióticos e simbiótico sobre o desempenho zootécnico e morfometria intestinal de frangos de corte desafiados com Salmonella Enteritidis." Universidade Tecnológica Federal do Paraná, 2013. http://repositorio.utfpr.edu.br/jspui/handle/1/2800.

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No Brasil, nas últimas décadas uma das grandes preocupações são as toxinfecções alimentares, sendo que uma das mais preocupantes vem a estar relacionada com as salmonellas. Esta doença destaca-se com grande importância pela sua ampla e variada ocorrência no homem e em animais; em que as aves ocupam o ponto central na epidemiologia das Salmonellas entéricas, representando um reservatório de grande importância sanitária e difícil controle. A Salmonella Enteritidis que é um patógeno entérico pertencente à família Enterobateriaceae, vindo a ser entre os mais de 2.500 sorotipos de Salmonellas spp., uma das mais frequentes de origem alimentar descrita na literatura. Uma das medidas profiláticas que tem sido empregada para controlar a infecção desta doença na produção de aves inclui o uso de antibióticos, seleções genéticas de linhagens de frangos para melhor resposta imunológica, desenvolvimento de vacinas e uso de produtos probióticos por meio de inclusão competitiva. A principal preocupação com o uso contínuo de antibióticos, principalmente pelas diversas organizações mundiais, é quanto ao surgimento e disseminação de populações bacterianas patogênicas, que trazem riscos tanto para a saúde animal quanto humana. Procurando alternativas que garantam o desempenho produtivo e a segurança alimentar dos consumidores, temos os probióticos que são suplementos alimentares, normalmente presentes no trato gastrointestinal (ex.: Bacillus subtilis e Bacillus licheniformis). Quando administrados de forma correta produzem efeitos benéficos ao hospedeiro, favorecendo o equilíbrio de sua microbiótica intestinal, podendo ser constituídos por microorganismos de culturas definidas, indefinidas ou simbióticos. Contudo não dispomos de estudos que possam comprovar qual das constituições de probióticos é a mais eficaz no combate as salmonellas entéricas e na melhor obtenção do desempenho zootécnico, o que requer maiores estudos em relação as diferentes constituições de probióticos disponíveis e suas formas de utilização. O objetivo do presente estudo foi abordar por meio de uma revisão bibliográfica a utilização de probióticos e simbióticos como auxiliares na qualidade intestinal e ferramenta no combate a salmonella. Um segundo objetivo é elaborar um capítulo com um artigo intitulado: “Probióticos e Simbiótico sobre o desempenho zootécnico e morfometria intestinal de frangos de corte desafiados com Salmonella Enteritidis”.
In Brazil, in the last decades a of great concerns have been about the food poisoning, being that a of the most worrying comes to be related with the Salmonella. This disease stands out with great importance for its wide and varied occurrence in the man and animals; in which birds occupy the central point the epidemiology of Salmonella Enteric, representing a reservoir of great importance health and difficult to control. Salmonella Enteritidis is a pathogen belonging to the family intérico Enterobateriaceae, it comes to be among the more than 2,500 serotypes Salmonellas sp., one of the most common foodborne described in the literature. An prophylactic measures that is has been used to control the infection of the disease in poultry production, including antibiotics, selection of genetic strains of chickens to better immune response, development of the vaccine and use of probiotic products by inclusion competitive. The main concern with the continuous use of antibiotics, especially by various organizations worldwide is on the emergence and spread of pathogenic bacterial populations, bringing risks to both animal and human health. Seeking alternatives to ensure the production performance and food safety for consumers, we probiotcs foods supplements that are normally present in the gastrointestinal tract (ex.: Bacillus Subtilis e Bacillus Licheniformis), when they are administered correctly produce beneficial effects to the host, favoring the balance of their intestinal microbiota, may consist of microorganisms defined, undefined or synbiotics culture. However we do not have studies to prove which of the constitutions of probiotics is most effective in combating the Salmonella Enteric and in obtaining the best zootechinical performance, which requires larger studies regarding the different constitutions of probiotics available and ways of use. The aim of this study was approach by means of a bibliographic review the use of probiotics and synbiotics acting as auxiliary tool in combating intestinal Salmonella. A second goal is to develop a chapter with an article entitled: "Probiotics and synbiotic about zootechinical performance and intestinal morphometry of broilers challenged with Salmonella Enteritidis."

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Reynolds, William David 1948. "Reticuloendothelial clearance and gastrointestinal absorption of polystyrene latex particles: Possible applications to the external scanning of tumors." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/277804.

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The use of 153Sm-incorporated polystyrene latex particles for the external image scanning of tumors was simulated in four murine strains. Reticuloendothelial blood clearance and tissue localization of 0.5 mum and 1.0 mum fluorescent PSL was evaluated in RE-competent and RE-depressed mice following IV injection and oral particle administration. Intravenous injection of PSL revealed differences in blood clearance rates and tissue distribution patterns with respect to strain and particle size; an explanation based on genetic strain derivation is offered. RE depression in the Balb/c resulted in higher circulating blood levels of both particle sizes without affecting tissue distribution patterns; the use of dissimilarly sized particles for blocking and testing resulted in dramatic decreases in organ PSL concentrations and alterations in apparent kinetic rate constants. Balb/c blood levels of orally administered particles were increased and remained temporally constant while tissue concentrations were generally lower than IV-injected levels.

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35

Wright, Emma. "The effect of pathogens on honeybee learning and foraging behaviour." Thesis, University of Warwick, 2013. http://wrap.warwick.ac.uk/57266/.

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The European honeybee, Apis mellifera, is important economically not just for honey production but also as a pollinator. Bee pollinated plants contribute towards one third of the food eaten worldwide. However, honeybee numbers in some areas are declining. A range of interacting factors are thought to be involved, including pathogens and parasites, loss of forage, pesticide use, bad weather, and limited genetic variability. Pathogens are also known to cause changes in the behaviour of their hosts and these premortality and sublethal effects of disease may well play a role in colony declines and are the focus of this thesis. For individual bees the fungus Metarhizium anisopliae was used as a model pathogen and RT-Q-PCR was used to detect and quantify naturally occurring pathogens. In field colonies the level of infestation of the parasitic mite Varroa destructor was modified as a surrogate for disease load as the amounts of many viruses correlate with mite levels. Survival experiments showed that both disease load and forage availability had an effect on honeybee longevity and feeding the bees pollen increased their survival. Learning experiments showed that both the fungus and some of the bees’ naturally occurring pathogens caused changes in the learning ability of young adult and older forager bees. Young adult bees were better able to learn when infected with the fungus, possibly because it made them more responsive to the sucrose stimulus, whilst older forager bees where less able to learn when infected with the fungus. Harmonic radar was used to show that honeybee flight ability was affected by naturally occurring pathogens, especially deformed wing virus which caused bees to fly shorter distances and for shorter amounts of time than uninfected bees. Observation hives were used to study in-hive behaviour showing that bees with more pathogens were likely to start foraging earlier than healthier bees.

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Sullivan, Leigh. "Identifying digital dermatitis infection reservoirs in beef cattle and sheep." Thesis, University of Liverpool, 2015. http://livrepository.liverpool.ac.uk/2048942/.

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Digital dermatitis (DD) is a superficial infectious dermatitis of the digital skin of cattle and sheep that can be very painful, causing severe lameness in affected animals. Bovine digital dermatitis (BDD) in dairy cattle has now been reported in most countries they are farmed, and DD in sheep, known as contagious ovine digital dermatitis (CODD) is rapidly emerging as a severe infectious foot disease since first reports from the UK in 1997. Spirochaetes, of the genus Treponema have frequently been found in large numbers in BDD lesions and are now considered the primary causative bacteria of BDD. Three treponeme phylogroups are consistently isolated from dairy cattle BDD in the UK and the USA, which are known as Treponema medium- like, Treponema phagedenis- like spirochaetes and Treponema pedis. Over the past 40 years research has focused on dairy cattle BDD and overlooked whether the disease exists in beef cattle herds in the UK, and whether the same aetiological agents are causal. There is also limited information on the causative bacteriological agents of CODD. Furthermore, no definitive transmission routes or infection reservoirs of DD in either cattle or sheep had thus far been delineated, with only a single study finding a potential reservoir site of DD treponemes in the dairy cattle gastrointestinal (GI) tract. Using molecular bacteriological studies it was found that CODD and beef cattle BDD, as in dairy cattle BDD, show a high association with the three DD treponeme phylogroups. All CODD and beef BDD lesions investigated had at least one of the three DD treponeme phylogroups present in the lesions and these treponemes were also isolated from a high proportion of lesions. No DD treponemes were detected in healthy sheep or beef cattle foot tissue. Upon 16S rRNA gene sequence analysis all isolates showed a high similarity, if not 100% identity, to representatives of each treponeme phylogroup isolated from dairy cattle BDD lesions, indicating a shared aetiology between DD in all three animals. Additionally, the same treponeme bacteria were detected and isolated from a new undefined foot disease in dairy goats in the UK indicating that cross-species transmission of DD may have occurred causing DD infection in a previously unaffected domestic livestock species. To understand potential transmission routes and infection reservoirs of DD, the host GI tract and hoof trimming equipment were investigated. Of the sheep gingival (n= 40) and rectal tissues (n= 40), 1/40 gingival tissues were positive for DD- associated treponemes (T. pedis), and 3/40 rectal tissues (one containing T. medium- like and two tissues containing T. pedis). No DD- associated treponeme DNA was amplified from beef cattle rectal tissues (n= 40), however 4/40 beef gingival tissues were positive for DD- associated treponemes (all containing T. phagedenis- like). A T. phagedenis- like DD treponeme was isolated from the rectal tissue of a CODD symptomatic sheep. Beef cattle (n= 41) and sheep (n= 79) faeces failed to amplify DD- associated Treponema DNA. Twenty two treponemes were isolated from sheep faeces; however, upon phylogenetic analysis these clustered with considered non-pathogenic treponemes, which interestingly exhibited farm specific diversity in their 16S rRNA gene. Trimming equipment was tested after being used to trim cattle and sheep hooves, and subsequently after disinfection of equipment. Of the blades used to trim DD symptomatic animals (n= 26, cattle and sheep combined), 25/26 were found to be positive for at least one of the DD Treponema phylotypes. This figure was reduced to 10/26 (38%) after disinfection of the blades. Following culture of a swab, an isolate belonging to the T. phagedenis- like spirochaetes was isolated from a knife sample after trimming a DD positive cow. Beef cattle sera from DD positive and negative farms were investigated to understand whether beef cattle’s perceived lower prevalence of BDD in the UK is due to a lack of exposure to treponemes, or a protective immune response. Beef cattle from DD positive farms appeared to produce a strong immunological response to treponemes, compared with DD negative farm animal sera. Therefore the perceived lower prevalence of DD in beef cattle does not appear to be due to a protective response in these animals, but more likely due to a lack of exposure to DD treponemes. In conclusion, these studies have produced vital information describing DD in beef cattle and sheep and their respective aetiological agents allowing for more appropriate treatments in the future. Additionally, given the two potential transmission routes delineated from the data, effective actions can be taken to prevent the spread of DD within current hosts and to limit emergence into yet unknown additional host species.

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Agu, Chidozie Victor Agu. "Use of process design and metabolic engineering to enhance bioconversion of lignocellulosic biomass and glycerol to biofuels." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1480590331055825.

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38

Sarkis, Flávia. "Avaliação das condições microbiológicas de carnes de animais silvestres no município de São Paulo." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-16122002-135024/.

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O interesse por espécies animais não convencionais, para a suplementação de proteína animal, é crescente, particularmente nos países africanos e asiáticos, porém, a utilização dessas fontes de alimento ainda é pouco documentada e quase não se sabe sobre as condições microbiológicas das carnes disponíveis para consumo. Este estudo avaliou as condições microbiológicas das carnes de capivara (Hydrochaeris hydrochaeris), cateto (Tayassu tajacu) e javali (Sus scrofa scrofa) in natura comercializadas no Brasil, município de São Paulo. Um total de vinte e sete amostras de carne de capivara, cateto e javali foram analisadas em laboratório e verificado o grau de contaminação por mesófilos aeróbios totais, psicrotróficos, Staphylococcus aureus, Clostridium sulfito-redutores, coliformes totais e fecais e Salmonella. 22% das amostras de carne de cateto apresentaram-se impróprias para o consumo humano devido à presença de Salmonella. 11% das amostras das carnes de capivara e javali e 22% das amostras de cateto apresentaram contagens elevadas de S. aureus, maiores que o limite máximo estabelecido pela resolução RDC nº12 da Agência Nacional de Vigilância Sanitária (ANVISA) de 02 de janeiro de 2001, para produtos cárneos crus, resfriados ou congelados, uma vez que a resolução não cita tais padrões para carne in natura. Por apresentarem contagem de S. aureus superiores aos padrões estabelecidos, tais amostras são consideradas em condições higiênico-sanitárias insatisfatórias. A análise estatística descritiva apresentou um elevado coeficiente de variação entre as 9 amostras analisadas para cada tipo de carne. Esse alto grau de variação mostra que as condições microbiológicas das amostras não apresentaram uniformidade no decorrer das análises.
The interest for non-conventional animal species, for the supplementation of animal protein is growing, although this food source is little documented. This study has evaluated the microbiological conditions of capybara (Hydrochaeris hydrochaeris), collared peccary (Tayassu tajacu) and wild boar (Sus scrofa scrofa) raw meat sold in São Paulo city. A total of twenty-seven samples were evaluated in a laboratory to find out the contamination value by: mesophiles aerobic, psychrotrophs, Staphylococcus aureus, Clostridium sulfito-redutores, coliforms group and Salmonella. 22% of collared peccary meat samples were improper to human consumption due to the Salmonella presence. 11% of the samples of the capybara meats and boar and 22% of the collared peccary samples presented high counting of S. aureus, larger than the maximum limit established by the resolution RDC nº12 of the National Agency of Sanitary Surveillance (ANVISA) of January 02, 2001, for raw meat products, colds or frozen, once the resolution doesn't mention such patterns for raw meat. These samples showed unsatisfactory hygenic-sanitary conditions by presenting S. aureus counting higher than the maximum limit.

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Tadepalli, Sambasivarao. "Leukotoxin gene and activity in animal and human strains of Fusobacterium species." Diss., Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/302.

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40

Lindberg, Stina. "Evaluation of a genomic work flow for the detection of Bacillus subtilis in animal feed and food samples." Thesis, Uppsala University, Department of Medical Biochemistry and Microbiology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6345.

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Bacillus anthracis is one of the most feared agents of biological warfare and causes the

deadly disease called anthrax. SVA (statens veterinärmedicinska anstalt) is working on a

project together with SLV (statens livsmedelsverk) where the target is to find rapid and

effective detection methods for Bacillus anthracis in animal feed and food samples. Bacillus

subtilis, which is harmless, was used in this study as a model organism to Bacillus anthracis.

A known concentration of vegetative Bacillus subtilis was spiked in animal feed and food

samples. The genomic work flow was based on automated DNA isolation and real time PCR.

The aim of the study was to screen for inhibitory components in the animal feed and food

samples using two different DNA isolation robots; Magnatrix 8000 and Biorobot EZ1. The

results showed that DNA of high quality was extracted from the samples with both robots.

However, the CT-value generated by the real time PCR showed considerable variation

depending on the sample matrix. Some samples, for instance egg and liver, were problematic

and gave low concentrations and high CT-values probably due to inhibitory components in the

samples. Further studies will be needed to solve these problems and optimize the methods that

were used in this study.

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41

Ferronato, Bruno de Oliveira. "Phrynops geoffroanus (Testudines, Chelidae) em ambiente antrópico: perfil hematológico e microbiota oral." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-17072008-145434/.

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Phrynops geoffroanus é uma espécie de quelônio com ampla distribuição na América do Sul, ocupando diversos tipos de habitat, inclusive rios urbanos poluídos. Com o objetivo de se conhecer aspectos ecológicos da espécie em ambientes antropizados, durante os anos de 2006 e 2007 foi realizado um estudo na bacia do rio Piracicaba, tendo como sítios amostrais o rio Piracicaba e seu afluente o ribeirão Piracicamirim. Um dos temas deste estudo foi à avaliação de aspectos sanitários da espécie. Foi investigado o perfil hematológico dos cágados no rio Piracicaba e ribeirão Piracicamirim, e avaliado um índice de estresse (razão heterófilo/linfócito), que além dos dois corpos d\'água foi adicionado um grupo de animais provenientes de cativeiro, da Fundação Parque Zoológico de São Paulo. A diferença entre um rio de maior volume, Piracicaba, e seu afluente Piracicamirim, ambos poluídos e com diferentes históricos de ocupação do solo, pouco influenciaram nas variações dos dados hematológicos dos cágados e os animais não apresentaram nenhum sinal de enfermidade através dos resultados obtidos no hemograma. Estas análises foram o tema do primeiro capítulo desta dissertação. Outro aspecto sanitário avaliado foi a microbiota bacteriana oral dos cágados em ambos os corpos d\'água, abordado no segundo capítulo. As amostras foram incubadas a 25 e 37ºC. Avaliou-se a patogenicidade das bactérias tanto para os cágados quanto para seres humanos. Houve crescimento de bactérias patogênicas para o homem e para os animais e a bactéria mais prevalente a 37ºC foi a Escherichia coli. Apesar disso, os cágados não apresentaram sinal aparente de infecção. Estudos de longo prazo são recomendados para animais residentes em ambientes antropizados, monitorando-se o estado sanitário e aspectos ecológicos e demográficos.
Phrynops geoffroanus is a freshwater turtle species, with a wide distribution in South America, living in many types of habitats, including polluted urban rivers. During 2006 and 2007, aiming to study ecological aspects of the species in anthropogenic environments, it was conducted an investigation at Piracicaba River Basin, in two sample sites, the Piracicaba river and its tributary, Piracicamirim stream. One of the topics studied was a health assessment of the turtles. It was examined the blood profile in Piracicaba and Piracicamirim turtles and evaluated a measure of stress (heterophil/lymphocyte ratio), that had another study group besides the animals from the rivers, turtles in captivity from Sao Paulo Zoo Park Foundation. The difference between a large river, Piracicaba and its tributary Piracicamirim, both polluted and with different soil use and occupation had a little influence on turtles\' hematological variation, and the animals did not show any sign of disease through the blood profile examination. These evaluations were the subject of the thesis\' first chapter. Another part of the health assessment study, subject of the second chapter, was the oral microbiota investigation, performed in Piracicaba and Piracicamirim turtles. The samples were incubated at 25 and 37º Celsius, aiming to check the bacterium\'s pathogenicity for the animals and for humans. The results showed growth of pathogenic bacterium for both and the most prevalent bacteria at 37ºC was Escherichia coli. Although, the turtles did not show any sign of infection. Long-term studies are suggested for turtles living in anthropogenic environments to monitor their health status, demography and ecological issues.

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Nunes, Adriano Silva. "Ácido cítrico como promotor de crescimento para codornas." Universidade Federal de Sergipe, 2016. https://ri.ufs.br/handle/riufs/6400.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The studies about the use of antimicrobials has been intensified, due to the possibility of these antimicrobials being the cause of bacterial tolerance in human beings that consume products of animal origin. The organic acids stand out among the natural antimicrobials, performing similar effects to convencionals antimicrobials. Although, the citric acid stands out as a potential natural antimicrobial. Because the coturniculture follow the same trend of the poultry industry, which is growing, to keep production levels in farming systems to meet the market demand, the use of antimicrobials is necessary. Therefore, it is necessary to evaluate the effects of different levels of citric acid as a growth promoter in Japanese quail diets. To achieve this, a sensibility analysis was realized to verify if citric acid has the capacity to inhibit the bacterial growth of Eschrichia coli and Salmonella spp in vitro, and a field test to further examine its effects on the Japanese Quails' digestive tract bacterial growth, evaluate the impact the citric acid has on the manifestation of genes related to nutrients transportation, and intestinal antioxidant capacity; so that the adequate level of citric acid integration can be determined. The in vitro testing was realized utilizing three levels of citric acid (0,0%; 0,6% and 1,2%) to verify its impact on Eschrichia coli and Salmonella spp , which was none. The performance test was realized utlizing 450 nine days old quails divided in total random design with five treatments, nine iterations and 10 birds per unit. Was inert added so to keep the diets isoenergetic and isoproteinicm getting five levels of citric acid: 0,0; 0,3; 0,6; 0,9; and 1,2%. The trials spanned 35 dias and the testing protocols were approved by the ethics comitee. The citric acid had a impact on growth (P=0,01), feed conversion (P=0,05), as well as manifestation of the genes SGLT1 (P=0,01), GPX7 (P=0,01), and SOD (P=0,01). In conclusion, the citric acid did not inhibit Eschrichia coli and Salmonella spp growth in the in vitro tests; improves the manifestation of aminoacids transporter and Sodiumglucose cotransporter 1. The best citric acid level for growing laying quails diet is of 0,60%.
Os estudos quanto ao uso de antimicrobianos naturais vêm sendo intensificados devido à possibilidade dos antimicrobianos químicos causarem resistência bacteriana em humanos. Dentre os antimicrobianos naturais destacam-se os ácidos orgânicos por exercerem efeitos similares aos antimicrobianos convencionais, estimulando pesquisas com o ácido cítrico por ser um dos potenciais antimicrobianos naturais. Relaciona-se também o crescente desafio sanitário em razão do modo de criação intensivo e o maior risco sanitário, tornando o uso de antimicrobianos necessário. Por isso, avaliar os efeitos de diferentes níveis de ácido cítrico como promotor de crescimento em dietas de codornas japonesas é essencial. Para isso, realizou-se um ensaio de sensibilidade para verificar se o ácido cítrico pode inibir o crescimento bacteriano de Escherichia coli e Salmonella spp in vitro e um teste a campo a fim de verificar seus efeitos sobre o desempenho de codornas japonesas, quantificar o crescimento bacteriano no trato digestivo, avaliar a influência do ácido cítrico sobre a expressão de genes relacionados ao transporte de nutrientes e à capacidade antioxidante intestinal; para então determinar o nível adequado de inclusão do ácido cítrico. O ensaio in vitro foi realizado utilizando três níveis de ácido cítrico (0,0; 0,6 e 1,2%) a fim de verificar sua influência sobre Escherichia coli e Salmonella. Verificou-se que estes níveis não exerceram influência sobre as mesmas. O ensaio de desempenho foi realizado utilizando 450 codornas com nove dias de idade, distribuídas em delineamento inteiramente casualizado, dentro de cinco tratamentos, nove repetições e 10 aves por unidade experimental. As dietas foram isoenergéticas e isoprotéicas e cinco níveis de ácido cítrico foram testados: 0,0; 0,3; 0,6; 0,9 e 1,2%. O experimento teve duração de 35 dias. O ácido cítrico influenciou o ganho de peso (P=0,01), a conversão alimentar (P=0,05) e a expressão dos genes B0AT1 (P=0,01), SGLT1 (P=0,01), GPX 7 (P=0,01) e SOD (P=0,01). Conclui-se que o ácido cítrico não inibiu o crescimento de Escherichia coli e Salmonela sp. em ensaios in vitro; entretanto, melhora a expressão do transportador de aminoácidos e cotransportador sódio-glicose 1. O melhor nível de ácido cítrico em dietas para codornas de postura em crescimento é de 0,60%.

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43

Wang, Qiong. "Characterization of white spot syndrome virus of penaeid shrimp: Genomic cloning and sequencing, structural protein analyzing and sequencing, genetic diversity, pathology and virulence." Diss., The University of Arizona, 1999. http://hdl.handle.net/10150/284292.

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The purpose of this dissertation was to characterize virulence, genomic and protein composition of a newly emerged virus of penaeid shrimp: white spot syndrome virus (WSSV). A partial genomic library, covering approximately 30-50% of the genome, of WSSV isolated from crayfish Orconectes punctimanus, was constructed by digesting viral DNA with endonuclease ClaI and cloning into the system pBluescript-JM109. Three viral inserts of approximately 2.2 kb, 2.8 kb and 6.3 kb, named as QW245, CR44, and QW237 respectively, were sequenced and analyzed. Six geographic isolates of WSSV, from China, India, Thailand, South Carolina, Texas, as well as from crayfish obtained from the US National Zoo in Washington D.C. were compared by electron microscopy (TEM) and SDS-PAGE. All viral isolates contained three major polypeptides of 25, 23 and 19 kDa. A fourth major polypeptide at the 14.5 kDa position was observed in four of the viral isolates. The 19 kDa polypeptide of the crayfish WSSV appeared larger in size than that of the other isolates. Amino acid composition of four of the major structural polypeptides of the South Carolina WSSV was analyzed. The NH₂ terminal amino acids of the 25, 23 and 14.5 kDa polypeptides of the SC WSSV were sequenced as MDLSFTLSVVTA, MEFGNLTNLDVA, and VARGGKTKGRRG, respectively. The genomic composition of the six geographic isolates of WSSV were compared by combining the methods of restriction analysis using nine endonucleases AccI, BglII, ClaI, BamHI, EcoRI, HindII, HaeI, SacI, XhoI and Southern blot hybridization applying three digoxigenin-11-dUTP labeled WSSV genomic probes LN4, C42 and A6. No distinctive difference among five WSSV isolated from penaeid shrimp was detected; differences were observed in the crayfish isolate of WSSV. The virulence of the six geographic isolates of WSSV were compared by per os challenge of Litopenaeus vannamei postlarvae and juveniles, and Farfantepenaeus duorarum juveniles. The Texas WSSV caused higher and more rapid mortalities; the crayfish WSSV caused lower and less rapid mortalities. L. vannamei postlarvae and juveniles were very susceptible to WSSV infection, while Fa. duorarum juveniles showed moderate resistance.

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Alli, Zaman. "The assembly of hepatitis B virus core particles in transgenic tobacco, carrot and rice plants." Thesis, University of Ottawa (Canada), 2004. http://hdl.handle.net/10393/29072.

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The spread amongst humans of viral diseases such as acquired immunodeficiency syndrome (AIDS), hepatitis and severe acute respiratory syndrome (SARS) is alarming. A plant-based high fidelity production system is being developed with emphasis on producing antigens capable of being orally delivered to humans in plant packets. To test whether transgenic tobacco, carrot and rice plants can correctly process and assemble the hepatitis-B virus (HBV) core particle/antigen (HBcAg), they were transformed with a C-terminal truncated version of the HBcAg subunit coding sequence. Transgenic tobacco, carrot and rice plants processed the HBV subunits accurately indicating that these recombinant expression systems can be extended to produce other proteins at reduced costs. In the wild-type expression construct (H1); the enhanced cauliflower mosaic virus double 35S (CaMV-d35S) promoter was fused to the alfalfa mosaic virus RNA 4 (AMV-RNA4) sequence to achieve greater translation of a C-terminal truncated HBV core particle subunit. A second expression construct (H2) was plant-codon optimized to match the Arabidopsis thaliana plant genome codon preferences. A third codon-optimized expression construct (H3) had a KDEL (lysyl-aspartyl-glutamyl-leucine) encoded sequence. While a fourth expression construct (H4) included an extensin signal sequence in place of the AMV-RNA4 sequence. Western blotting analysis showed the presence of the HBcAg in transgenic tobacco, carrot and rice plants. The HBcAg levels increased from the H1 to the H4 transgenic tobacco lines. Plant codon-optimization of the HBcAg sequence and addition of the KDEL encoded sequence led to higher levels of HBcAg. The most effective modification was observed when the extensin signal sequence replaced the AMV-RNA4 translation enhancer sequence resulting in the highest observed yields of HBcAg in both the leaves and seeds of the best H4 tobacco plant. In edible plants, higher levels of HBcAg were observed in carrot roots as opposed to carrot leaves and in rice seeds as opposed to rice leaves. Further analyses via electron microscopy indicated that the HBV subunits had assembled into virus-like particles of 25--30 nm diameter in all three plant systems. Therefore, these studies may aid in the global quest to develop cheap, safe and effective vaccines.

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Oetting, Liliana Lotufo. "Extratos vegetais como promotores do crescimento de leitões recém-desmamados." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-09112005-140849/.

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Apesar da comprovada capacidade de melhorar o desempenho de suínos, o uso de antimicrobianos como promotores do crescimento vem sendo progressivamente restringido em diversos países. As novas regulamentações têm forçado a procura por alternativas ao uso de antibióticos e quimioterápicos como promotores do crescimento de suínos. Os extratos vegetais constituem uma dessas alternativas pesquisadas. Sendo assim, o objetivo do trabalho foi avaliar os efeitos de antimicrobianos e extratos vegetais sobre a digestibilidade aparente dos nutrientes, desempenho, morfometria dos órgãos, histologia do epitélio intestinal, microbiologia intestinal e frequência de diarréia de leitões recém-desmamados. Foram realizados três experimentos em blocos casualizados, nos quais foram testados, durante 35 dias, cinco tratamentos: controle - ração basal; antimicrobiano - basal com bacitracina de zinco, olaquindox e colistina (50 ppm de cada); extrato vegetal A, B e C - basal com 700, 1200 e 2100 ppm de extrato vegetal, respectivamente. O extrato vegetal foi constituído de quantidades iguais de óleo essencial de cravo, tomilho, orégano, eugenol e carvacrol. Foram utilizados 40 leitões em cada experimento, com idades iniciais e finais de, respectivamente, 21 e 56 dias. Foram alocados dois leitões (um macho castrado e uma fêmea) em cada baia (unidade experimental). No ensaio de digestibilidade (Experimento I) utilizou-se o método da coleta parcial de fezes, tendo o óxido crômico (Cr2O3) como marcador. Ao final do Experimento I, um animal de cada unidade experimental foi abatido para análise de morfometria dos órgãos e coleta de amostras do epitélio intestinal para análise histológica e microbiológica. Nos Experimentos I, II e III, foram medidas a frequência de diarréia e as variáveis de desempenho. A digestibilidade da matéria seca foi maior (P<0,05) para o tratamento com extratos vegetais em relação ao tratamento controle e com antimicrobianos. Durante os períodos de 1 a 14 e 1 a 35 dias de experimentação, o tratamento antimicrobiano apresentou melhores resultados (P<0,05) de peso vivo, consumo diário de ração e ganho diário de peso que os demais tratamentos. Dentre os níveis de extratos vegetais, o maior nível de inclusão foi o que proporcionou melhores resultados de desempenho. Na análise de morfometria dos órgãos, foram encontradas diferenças (P<0,05) entre os tratamentos apenas para o peso relativo do trato gastrintestinal total e do intestino delgado vazio, sendo que os melhores (menores) resultados foram obtidos para os animais suplementados com antimicrobianos. Para a histologia do epitélio intestinal, novamente os melhores resultados foram obtidos para o tratamento com antimicrobianos, tendo apresentado maior altura de vilosidade (P<0,05) e menor relação altura de vilosidade e profundidade de cripta do íleo que os tratamentos com extratos vegetais. Não foram encontradas diferenças significativas (P>0,05) para os resultados de microbiologia intestinal. A frequência de diarréia dos animais que receberam antimicrobianos foi inferior (P<0,05) àquela do tratamento controle ou extratos vegetais no período de 1 a 35 dias de experimentação, indicando eficácia dos antimicrobianos em controlar a diarréia. Os extratos vegetais apresentaram resultados intermediários entre o tratamento controle e com antimicrobianos para essa variável.
The use of antimicrobials as growth promoters of swine has been gradually restricted in many countries. The new regulations have forced the search for alternatives to the antibiotic use as growth promoters for swine. The herbal extracts are one of these alternatives. The purpose of this work was to evaluate the antimicrobial agents and herbal extracts as growth promoters, based on intestinal morphology, histology, microbiology, digestibility, fecal score, and on performance of weanling pigs. Three randomized complete block design experiments were carried out to compare five treatments: control - basal diet; antimicrobial - basal diet plus Zn bacitracin, olaquindox, and colistin (50 ppm of each); herbal extract A, B and C - basal diet plus 700 ppm, 1200 ppm and 2100 ppm of herbal extract, respectively. The herbal extract consisted of a mixture of equal amounts of essential oils of thyme, clove, oregano, eugenol and carvacrol. In each Experiment, forty 21-d-weaned pigs were allotted to 20 suspended pens, with two pigs (a castrated male and a female) per pen (experimental unit) and four replications per treatment. Digestibility assay (Experiment I) was conducted using chromic oxide (Cr2O3) as fecal marker. On 35th day of experimental period, an animal of each experimental unit was slaughtered for morphological analysis and samples of the intestine epithelium were collected for histological and microbiological analysis. Performance data and fecal score of pigs were collected from Experiments I, II and III. The herbal extracts increased (P<.05) the dry matter apparent digestibility of the diet compared to control and antimicrobial treatments. The antimicrobial agents improved (P<.05) body weight, feed intake and average daily gain of weanling pigs during 1 to 14 and 1 to 35 days of experimental period compared to control and herbal extract. Among all levels of herbal extract, higher levels showed better performance results. The antimicrobial treatment improved the relative weights of the intestinal tract and empty small intestine (P<.05) and improved ileum villus height and the ratio of ileum villus height:crypt depth of animals. There was no statistical difference (P>.05) in microbiological analysis. During 1 to 35 days of experimental period, incidence of diarrhoea of pigs fed antimicrobials was statisticaly lower (P<.05) than those fed control or herbal extract diet, suggesting the efficacy of antimicrobials in diarrhoea control. Pigs fed herbal extract showed intermediary results between antimicrobial and control diets for this variable.

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Hackmann, Timothy John. "Responses of Rumen Microbes to Excess Carbohydrate." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1364922613.

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47

Sadik, Mohamad Shabir 1959. "MICROBIAL PROTEIN FLOW TO THE SMALL INTESTINE OF COWS FED DIFFERENT PROTEIN SUPPLEMENTS." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/292012.

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Three duodenally cannulated lactating Holstein cows fed cotton-seed meal (CSM), corn gluten meal (CGM) or blood meal (BM) as protein supplement were used in a 3 x 3 Latin Square experiment to determine microbial crude protein (MCP) in duodenal digesta. Diets, formulated to contain 15% crude protein (CP) on a dry matter basis, consited of 60% concentrate, 31% corn silage and 9% alfalfa hay. Chromium oxide was employed as flow marker. Microbial protein fraction of digesta CP (MCP/DCP) was estimated by three microbial markers: ¹⁵N, diaminopimelic acid (DAP) and ribonucleic acid (RNA). The isotopic method gave the most reliable results. Variability was higher with DAP and RNA. Results from RNA were lower (P < .01) and unreasonable. Based on ¹⁵N, MCP/DCP differed among treatments (P < .10) with means of 61.5, 59.4, and 50.0% for CSM, CGM, and BM, respectively, but differences were not significant for absolute amounts of total CP and MCP in duodenal digesta.

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48

Wlodarski, Leticia. "Determinação e quantificação de protozoários ciliados e bactérias do rúmen de bovinos em pastagens temperadas e tropicais." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2457.

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CAPES
O objetivo do presente trabalho foi identificar e quantificar os protozoários ciliados e bactérias do rúmen de bovinos cruzados (Europeu x Nelore), com média de 2,5 anos, alimentados em pastagens de inverno (Azevém e Aveia + Azevém) e verão (Brachiaria spp. e Brachiaria spp. + Esrela Africana). Amostras de conteúdo ruminal foram obtidas do centro da massa ruminal, após o abate dos animais. A contagem de bactérias totais (CBT), para as frações sólida e para líquida, foi realizada em placas com auxílio de contador de colônias manual. Para a análise morfológica empregou-se a técnica de coloração de Gram e a leitura das lâminas foi feita em microscópio óptico com objetiva de 100x, sendo as bactérias classificadas em cocos e bacilos, gram positivos e gram negativos. A avaliação da atividade fermentativa foi evidenciada pelo crescimento de colônias com coloração rósea atravéz de uma fonte de carboidrato. A quantificação e identificação dos gêneros de ciliados foram realizadas em câmara Sedgewick-Rafter em microscopia ótica. Foi determinado o teor de Matéria Seca, Proteína Bruta, Matéria Mineral, Fibra em Detergente Neutro e Fibra em Detergente Ácido, Digestibilidade In Vitro na Matéria Seca, Lignina, Celulose, Hemicelulose. O delineamento experimental foi inteiramente casualizado, com quatro tratamentos e 10 repetições para cada tratamento. Os dados foram submetidos à análise por meio da metodologia de Modelos Lineares, generalizados, com distribuição Poisson (1%) e foi utilizado o procedimento GENMOD. Foram observadas bactérias Gram positivas e negativas, nas formas cocos e bacilos e 11 gêneros de protozoários ciliados, sendo Diplodinium o gênero predominante. A maior concentração de bactérias foi encontrada nas forrageiras de inverno (494,8 x1010 mL-1), com maior intensidade na pastagem de Azevém. Nos protozoários ciliados, maior concentração foi observada no verão (200,70 x104 mL-1), principalmente na pastagem de Brachiaria spp.
The objective of the present work was to identify and quantify the ciliate protozoa and crossbovine rumen bacteria (European x Nellore), with an average of 2.5 years, fed on winter pastures (Azevém and Aveia + Azevém) and summer (Brachiaria spp And Brachiaria spp. + Esrala Africana). Samples of ruminal contents were obtained from the center of the ruminal mass, after the slaughter of the animals. The total bacterial count (CBT), for solid and liquid fractions, was performed in plates with the aid of a manual colony counter. For the morphological analysis the Gram staining technique was used and the slides were read under an optical microscope with objective of 100x, being the bacteria classified in cocci and bacilli, gram positive and gram negative. The evaluation of the fermentative activity was evidenced by the growth of colonies with pink coloration through a carbohydrate source. The quantification and identification of ciliate genera were performed in Sedgewick-Rafter chamber under optical microscopy. The content of Dry Matter, Crude Protein, Mineral Matter, Neutral Detergent Fiber and Acid Detergent Fiber, In Vitro Digestibility in Dry Matter, Lignin, Cellulose and Hemicellulose were determined. The experimental design was completely randomized, with four treatments and 10 replicates for each treatment. The data were submitted to analysis using the methodology of Linear Models, generalized with Poisson distribution (1%) and the GENMOD procedure was used. Gram positive and negative bacteria were observed, in the forms cocci and bacilli and 11 genera of ciliate protozoa, being Diplodinium the predominant genus. The highest concentration of bacteria was found in winter forages (494.8 x1010 mL-1), with higher intensity in the Azevém pasture. In the ciliate protozoa, higher concentration was observed in the summer (200.70 x 10 4 mL-1), mainly in Brachiaria spp.

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49

Wanderley, Marly Cristina Pinto. "Ocorrência de Escherichia coli resistente a antimicrobianos em diferentes sítios corporais em uma população diversa de gatos saudáveis /." Jaboticabal, 2015. http://hdl.handle.net/11449/128180.

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Orientador: José Moacir Marin
Banca: Maria Cristina Monteiro de Souza Gugelmin
Banca: Maria de Fátima Martins
Banca: Janete Aparecida Desidério
Banca: Everlon Cid Rigobelo
Resumo: Animais de estimação e humanos têm contato muito próximo, o que favorece o intercâmbio de micro-organismos de suas microbiotas, como, por exemplo, de Escherichia coli (E. coli), que é prevalente como simbionte na microbiota de humanos e animais. Paradoxalmente, também é reconhecida como micro-organismo com alto impacto clínico, devido à elevada ocorrência de cepas resistentes às múltiplas drogas. O alto consumo de antimicrobianos, observado tanto na medicina humana, quanto na veterinária, representa forte pressão de seleção também em bactérias da microbiota. Desta forma, o presente estudo investiga a prevalência da resistência antimicrobiana e analisa a filogenia de cepas de E. coli isoladas de abdômen/dorso, boca, genitália externa e reto de gatos saudáveis, relacionando-as com sua população de origem. A proximidade da residência do tutor do gato em relação a locais onde o uso de agentes antimicrobianos é rotineiro foi usada como critério para a formação de três populações, constituídas da seguinte forma: por animais cujos tutores residem próximos a hospitais ou postos de saúde humana (CSH); próximos às clínicas veterinárias (CSV) e sem proximidade com esses locais (SMP). Foram coletadas 325 amostras a partir de 65 gatos, das quais foram obtidas 231 cepas de E. coli, provenientes de todos os sítios corporais pesquisados. O reto originou a maioria dos isolados susceptíveis. A população CSH exibiu maiores frequências de resistência à ampicilina, cefazolina e cefalotina, assim como a maioria dos fenótipos de resistência às múltiplas drogas (MDR), a população CSV foi mais resistente ao cotrimoxazol. Maior similaridade de resistência foi observada entre cepas isoladas do reto e genitália externa e, entre as isoladas do abdômen/dorso e boca. Fenótipo ESBL (Extended Spectrum Betalactamases - Beta lactamases de espectro ampliado) ocorreu em duas cepas (0,88%). Classificação filogenética...
Abstract: Pets and humans have close contact, allowing the exchange of micro-organisms of their microbiota as Escherichia coli (E. coli), which is prevalent as a simbionte of the human and animal microbiota. Paradoxally, it is also recognized as a high clinic impact, due to a high ocurrence of multiple drugs resintant strains. The high usage of antimicrobials agents, observed in the human medicine, as well as in the veterinary medicine, represents a high selection pressure in microbiota bacteria. This way, the present study investigates the prevalence of the antimicrobian resistance and analizes the phylogenyic origin of E. coli isolated from abdomen/back, mouth, outer genitalia and rectum of healthy cats, relating these data with the original population. The proximity of the cat tutor 's residence in relation to places where the use of antimicrobial agents is routine was used as a criterion for the formation of three groups such as follows:constituted by animals that live close to hospitals and Health Human Care (CSH); close to veterinary clinics (CSV) and without proximity to these places (SMP). 325 samples were collected from 65 cats, which were obtained 231 cepas of E. coli originated from all the researched body sites. The rectum originated most of the susceptible isolated. The CSH population showed greater resistance frequency to ampicillin, cefazoline and cephalotin as well as most of multiple resistance drugs (MDR) phenotype, the CSV population was more resistant to the cotrimoxazol. A greater resistance similarity was observed in isolated cepas of the rectum and outer genitalia, and between the abdomen/back and mouth isolates. The phenotype ESBL (Extended Spectrum Betalactamase) ocurred in two strains (0,88%). The phylogenetic classification, performed by Triplex PCR, in 191 strains, showed the presence of all the researched phylogenetic groups (A, B1, B2, and D), the majority originated from group A (49,7%) in all the populations ...
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50

Wanderley, Marly Cristina Pinto [UNESP]. "Ocorrência de Escherichia coli resistente a antimicrobianos em diferentes sítios corporais em uma população diversa de gatos saudáveis." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/128180.

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Made available in DSpace on 2015-10-06T13:03:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-05-28. Added 1 bitstream(s) on 2015-10-06T13:18:06Z : No. of bitstreams: 1 000848538_20160128.pdf: 292719 bytes, checksum: dd4dcd81cbdf6b048dfdea1c04771f4a (MD5) Bitstreams deleted on 2016-01-28T17:44:56Z: 000848538_20160128.pdf,. Added 1 bitstream(s) on 2016-01-28T17:45:37Z : No. of bitstreams: 1 000848538.pdf: 1723555 bytes, checksum: e8a899ba78bf6c6438ecf1784ef24ccf (MD5)
Animais de estimação e humanos têm contato muito próximo, o que favorece o intercâmbio de micro-organismos de suas microbiotas, como, por exemplo, de Escherichia coli (E. coli), que é prevalente como simbionte na microbiota de humanos e animais. Paradoxalmente, também é reconhecida como micro-organismo com alto impacto clínico, devido à elevada ocorrência de cepas resistentes às múltiplas drogas. O alto consumo de antimicrobianos, observado tanto na medicina humana, quanto na veterinária, representa forte pressão de seleção também em bactérias da microbiota. Desta forma, o presente estudo investiga a prevalência da resistência antimicrobiana e analisa a filogenia de cepas de E. coli isoladas de abdômen/dorso, boca, genitália externa e reto de gatos saudáveis, relacionando-as com sua população de origem. A proximidade da residência do tutor do gato em relação a locais onde o uso de agentes antimicrobianos é rotineiro foi usada como critério para a formação de três populações, constituídas da seguinte forma: por animais cujos tutores residem próximos a hospitais ou postos de saúde humana (CSH); próximos às clínicas veterinárias (CSV) e sem proximidade com esses locais (SMP). Foram coletadas 325 amostras a partir de 65 gatos, das quais foram obtidas 231 cepas de E. coli, provenientes de todos os sítios corporais pesquisados. O reto originou a maioria dos isolados susceptíveis. A população CSH exibiu maiores frequências de resistência à ampicilina, cefazolina e cefalotina, assim como a maioria dos fenótipos de resistência às múltiplas drogas (MDR), a população CSV foi mais resistente ao cotrimoxazol. Maior similaridade de resistência foi observada entre cepas isoladas do reto e genitália externa e, entre as isoladas do abdômen/dorso e boca. Fenótipo ESBL (Extended Spectrum Betalactamases - Beta lactamases de espectro ampliado) ocorreu em duas cepas (0,88%). Classificação filogenética...
Pets and humans have close contact, allowing the exchange of micro-organisms of their microbiota as Escherichia coli (E. coli), which is prevalent as a simbionte of the human and animal microbiota. Paradoxally, it is also recognized as a high clinic impact, due to a high ocurrence of multiple drugs resintant strains. The high usage of antimicrobials agents, observed in the human medicine, as well as in the veterinary medicine, represents a high selection pressure in microbiota bacteria. This way, the present study investigates the prevalence of the antimicrobian resistance and analizes the phylogenyic origin of E. coli isolated from abdomen/back, mouth, outer genitalia and rectum of healthy cats, relating these data with the original population. The proximity of the cat tutor 's residence in relation to places where the use of antimicrobial agents is routine was used as a criterion for the formation of three groups such as follows:constituted by animals that live close to hospitals and Health Human Care (CSH); close to veterinary clinics (CSV) and without proximity to these places (SMP). 325 samples were collected from 65 cats, which were obtained 231 cepas of E. coli originated from all the researched body sites. The rectum originated most of the susceptible isolated. The CSH population showed greater resistance frequency to ampicillin, cefazoline and cephalotin as well as most of multiple resistance drugs (MDR) phenotype, the CSV population was more resistant to the cotrimoxazol. A greater resistance similarity was observed in isolated cepas of the rectum and outer genitalia, and between the abdomen/back and mouth isolates. The phenotype ESBL (Extended Spectrum Betalactamase) ocurred in two strains (0,88%). The phylogenetic classification, performed by Triplex PCR, in 191 strains, showed the presence of all the researched phylogenetic groups (A, B1, B2, and D), the majority originated from group A (49,7%) in all the populations ...

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