[Truncated abstract] The collection of buccal cells is common practise in the epidemiological and forensic science. Unlike venipuncture collection of blood; it is a safer, non-invasive method for collection of biological material. The methods by which these cells are collected from the inner cheek of an individual and stored are the key elements in preserving DNA. Typically, forensic samples require long term storage. Samples are commonly collected on cotton swabs and stored moist at low to ultra-low temperatures (less than -20oC). Although this is the method of choice in most forensic facilities, there are drawbacks. The samples are inherently contaminated with microflora within the oral cavity and the moisture allows a plethora of microorganisms to grow. As the time frame that has elapsed from collection to storage increases, there is an exponential increase in bacterial cells. Storage of containers containing swabs coated with cells at temperatures below 20oC is also costly due to requirements for large freezers which are running and monitored over 24 hours. In the pass 10 to 15 years, researchers have focussed on alternative ways to store buccal cells. The FTA card system by Whatman is one such development. The FTA card is unique in that it provides a means for the collection of buccal cells for storage at room temperature. DNA profiling from samples stored in this way for 11 years has been successfully achieved. The filter paper matrix of the FTA card binds and subsequently lyses cells. ... (2) The second component of this thesis describes a study which subjected cells on buccal swabs to various conditions of increased temperature over periods of time to establish if DNA could be amplified. The aim was to mimic exposure to the vigours of field conditions, particularly in the extreme local environments that prevail in the United Arab Emirates. a. Initially, buccal cells stored at -20oC over 360 days were used to mimic standard archiving procedures. The cells were subsequently transferred to FTA cards, amplified and profiled by using ABI AmpFLSTR Identifiler PCR Amplification Kit (Applied Biosystems, Foster City, CA). Complete STR profiles were successfully recovered from the archived swabs. In most cases 100% of alleles were recovered, suggesting that it is feasible to transfer DNA from properly archived buccal swabs to FTA cards. b. The second phase involved the storage of fresh swabs that had been artificially aged by using incubation temperatures ranging from 40oC to 100oC. Partial profiles resulted from artificially aged samples, indicating that the prevailing conditions prior to low temperature storage of the swabs plays an important role in ensuring cellular integrity and thus, DNA quality. Results from this study suggest that it is possible for biological samples stored under correct conditions to be transferred from swabs to FTA card. In combination, the two chapters presented in this study show that it is feasible to transfer achieved forensic biology samples from swabs to the FTA card system. However, it is necessary to ensure that the samples are treated in the correct manner so as to minimise contamination from external sources and to maintain the correct environmental state to maintain intact cells and usable DNA.

Background: The monitoring of infectious diseases like the porcine reproductive and respiratory syndrome (PRRS) using pen-wise oral fluid samples becomes more and more established. The collection of individual oral fluid, which would be useful in the monitoring of PRRSV negative boar studs, is rather difficult. The aim of the study was to test two methods for individual oral fluid collection from pigs and to evaluate the specificity of a commercial ELISA for detection of PRRSV antibodies in these sample matrices. For this reason, 334 serum samples from PRRSV negative pigs (group 1) and 71 serum samples from PRRSV positive pigs (group 2) were tested for PRRSV antibodies with a commercial ELISA. Individual oral fluid was collected with a cotton gauze swab from 311 pigs from group 1 and 39 pigs from group 2. Furthermore, 312 oral fluid samples from group 1 and 67 oral fluid samples from group 2 were taken with a self-drying foam swab (GenoTube). The recollected oral fluid was then analysed twice with a commercial ELISA for detection of PRRSV antibodies in oral fluid.

No description available.

This study focuses on emerging E. coil serotypes and has developed methods for the isolation and identification of non-0157 STEC and EPEC. A basal medium for the isolation of these pathogens was developed as well as a serogroup specific PCR assay for the detection of the 02 serogroup. These culture and molecular based techniques have proven to be valuable in the detection, identification, and epidemiological investigation of these groups of emerging pathogens. These methods were applied to 1) a farm study, whereby samples (faecal and soil) and 2) an abattoir study, whereby samples (hide and carcass) were analysed for the presence of non-0157 STEC and EPEC. Isolates were subsequently characterised in terms of serotype/serogroup and virulence markers. The data generated by this work has illustrated the extent of non-0157 STEC and EPEC contamination in the farm and abattoir environments, thus providing scientific background upon which control strategies may be based.

Made available in DSpace on 2014-07-29T15:07:29Z (GMT). No. of bitstreams: 1 Dissertacao_Dunya_Moraes.pdf: 432826 bytes, checksum: 63ffc1c5c83c7f760eb90cca2350b35f (MD5) Previous issue date: 2010-03-26 / The objective of this research to investigate the presence of Salmonella sp. in raw materials of animal origin used in the manufacture of feed for broilers, in diets collected directly from bird feeders, and in organs ceca contents and liners carry case for newly hatched chicks, in environmental samples, in samples from swabs of the hands of officials of the farm and slaughterhouse samples and classify and determine the resistance of strains of Salmonella sp. found, before the action of chemotherapeutic nine. For data analysis was descriptive frequency results. 1200 samples were collected from flour and Salmonella sp. was found in 10.5% of samples with a predominance of serovar Enteritidis. The frequency of bacteria in meat meal was 12%, 6.8% in blood, the feathers of 4.3% and 14.6% in the viscera. Were also isolated Salmonella Cerro, Salmonella Montevideo, Salmonella anatum, Salmonella Tennessee, and Salmonella typhimurium among others. Regarding the resistance of strains found in the various categories of flour was observed resistance to sulfonamides, neomycin, tetracycline, sulphamethoxazole-to trimetopim and florfenicol. Of the three strains of bacteria isolated from two diets were of a Salmonella enteritidis and S. Anatum, showing resistance to sulfonamides and neomycin. Of the 32 batches of newly hatched chicks 9.4% were positive for Salmonella and 32 batches of liners carrying case 9.4%. Environmental samples, before bed accommodation, swabs of feeder and drinker and the drinking water of birds tested negative for Salmonella sp .. Drag swabs of poultry manure, and samples Alphitobius diaperinus swabs from the hands of officials of the farms had a frequency of 12.5%, 12.5% and 6.5% respectively. In samples from swabs of drag serovar Enteritidis was the most frequent and catfishes of the samples and swabs of hands was the only serovar isolated. In samples from slaughterhouse 26.7% of the lots from crop and 33.3% of batches of ceca were positive for Salmonella sp .. Regarding the resistance of strains, there was resistance sulfonamides, the amoxicillin and enrofloxacin in samples of newly hatched chicks and amoxicillin in the samples of liners carrying case. In drag swabs and samples of catfishes, the bacteria were resistant to sulfonamides. In samples from crop, were resistant to sulfonamide and enrofloxacin and the caeca to sulfonamides, the trimetopim-sulphamethoxazole, tetracycline, amoxicillin and ampicillin to. / Objetivou-se com esta pesquisa investigar a presença de Salmonella sp. em matérias primas de origem animal utilizadas na fabricação de rações de frangos de corte, em rações coletadas diretamente dos comedouros das aves, em órgãos e conteúdos de cecos e forros de caixa de transporte de pintos de um dia, em amostras ambientais, em amostras de suabes de mãos de funcionários de granjas e em amostras de abatedouro bem como tipificar e determinar o perfil de resistência das cepas de Salmonella sp. encontradas, frente à ação de nove quimioterápicos. Para análise dos dados foi feita freqüência descritiva dos resultados encontrados. Coletou-se 1200 amostras de farinhas e Salmonella sp. foi encontrada em 10,5% das amostras com predominância do sorovar Enteritidis. A freqüência da bactéria em farinhas de carne foi de 12%, nas de sangue 6,8%, nas de penas 4,3% e nas de vísceras 14,6%. Foram isoladas também Salmonella Cerro, Salmonella Montevideo, Salmonella Anatum, Salmonella Tennessee e Salmonella Typhimurium entre outras. Em relação ao perfil de resistência das cepas encontradas nas diversas categorias de farinhas foi observado resistência à sulfonamidas, à neomicina, à tetraciclina, ao trimetopim-sulfametoxasol e ao florfenicol. Das três cepas da bactéria isoladas de rações duas eram de Salmonella Enteritidis e uma de S. Anatum, apresentando resistência à sulfonamidas e à neomicina. Dos 32 lotes de pintos de um dia 9,4% apresentaram positividade para Salmonella e dos 32 lotes de forros de caixa de transporte 9,4%. As amostras ambientais, cama antes do alojamento, suabes de comedouro e de bebedouro e água de bebida das aves apresentaram resultados negativos para Salmonella sp.. Suabes de arrasto de cama de aviários, amostras de Alphitobius diaperinus e suabes de mãos de funcionários das granjas apresentaram freqüência de 12,5%, 12,5% e 6,5% respectivamente. Nas amostras de suabes de arrasto o sorovar Enteritidis foi o mais freqüente e nas amostras de cascudinhos e suabes de mãos foi o único sorovar isolado. Nas amostras de abatedouro 26,7% dos lotes de inglúvio e 33,3% dos lotes de cecos foram positivos para Salmonella sp.. Com relação ao perfil de resistência das cepas isoladas, observou-se resistência à sulfonamidas, à amoxacilina e à enrofloxacina nas amostras de pintos de um dia e à amoxacilina nas amostras de forros de caixa de transporte. Nos suabes de arrasto e amostras de cascudinhos, as bactérias foram resistentes à sulfonamidas. Nas amostras de inglúvios, foi observada resistência à sulfonamidas e à enrofloxacina e nos cecos à sulfonamidas, ao trimetopim-sulfametoxasol, à tetraciclina, à amoxacilina e à ampicilina.