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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Indicadores de qualidade, pesquisa de marcadores de virulência e multirresistência aos antimicrobianos em estirpes de Staphylococcus spp. em leite de origem bovina produzido no sistema orgânico

Siqueira, Amanda Keller [UNESP] 27 May 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-05-27Bitstream added on 2014-06-13T18:46:42Z : No. of bitstreams: 1 siqueira_ak_dr_botfmvz.pdf: 2732300 bytes, checksum: ef925129d37522aac4be31a9933f5412 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O presente estudo investigou a qualidade microbiológica do leite de duas pequenas propriedades orgânicas (I e II) do estado de São Paulo, bem como a presença de marcadores de virulência de Staphylococcus spp. e isolados bacterianos multirresistentes aos antimicrobianos. Foram analisados os principais constituintes do leite, contagem bacteriana total, nível de celularidade, além da presença de resíduos de antimicrobianos, com base nas Normativas 051 e 064 do MAPA. O efeito das estações do ano sobre os parâmetros pesquisados também foi considerado. Foram realizadas 12 colheitas em cada uma das duas propriedades, das quais 12 mensais dos latões e quatro trimestrais de todos os animais. No total foram colhidas amostras de leite de 178 animais (259 tetos). Destes, 125/259 (48,27%) tetos acusaram mastite subclínica no CMT, 2/259 (0,77%) tetos mastite clínica e 132/259 (50,96%) foram negativos. A mediana da CCS das duas propriedades variou entre 311,67 x 1000 céls/mL e 447,83 x 1000 céls/mL e a CBT variou entre 25,4 x 1000 UFC/mL e 141,63 x 1000 UFC/mL, sem influência das estações do ano. Os principais constituintes do leite mantiveram-se dentro dos parâmetros estabelecidos. Das 86 amostras de leite da propriedade I, seis (6,97%) foram positivas para a presença de resíduos de antimicrobianos, enquanto das 173 amostras da propriedade II, 16 (9,24%) foram positivas. Staphylococcus spp. e Corynebacterium bovis foram os micro-organismos mais freqüentes, isolados em 58/259 (22,39%) e 50/259 (19,30%), respectivamente, de amostras de leite dos animais. Das 58 linhagens de Staphylococcus spp., 48 (82,76%) foram classificadas como coagulase positivas (ECPs) e 10 (17,24%) como coagulase negativas (ECNs). Para os ECPs, S. intermedius foi mais frequente (46,56%), seguido por S. aureus (22,42%). Dentre os ECNs, S. warneri foi caracterizado em 13,80% das linhagens. A sensibilidade das... / The present study investigated the microbiological quality of milk from two small organic properties (I and II) from São Paulo State, as well as the presence of virulence markers of Staphylococcus spp. and multidrug-resistant isolates to antimicrobials. We analyzed the major milk components, total bacterial count, level of cellularity and the presence of antimicrobial residues, based on Normative 051 and 064 MAPA, Brazil. The effect of seasons on the studied parameters was also considered. Twenty harvests were conducted in each of the two properties, including 12 monthly and four quarterly samples of all animals. In total we collected milk samples from 178 animals (259 mammary glands). Of these, 125/259 (48.27%) mammary glands showed subclinical mastitis on CMT, 2/259 (0.77%) clinical mastitis and 132/259 (50.96%) had been negative. The median of SCC of the two properties varied between 311.67 x 1000 cells/mL and 447.83 x 1000 cells/mL and TBC showed between 25.4 x 1000 CFU/mL and 141.63 x 1000 CFU/mL, without influence of the seasons. The contents of the main milk components remained with the established standards. Of the 86 samples of milk from the property I, six (6.97%) were positive for the presence of antimicrobial residues, while from 173 samples of property II, 16 (9.24%) were positive. Staphylococcus spp. and Corynebacterium bovis were the most frequent microorganisms isolated in 58/259 (22.39%) and 50/259 (19.30%), respectively, in the milk samples of animals. Of the 58 strains of Staphylococcus spp., 48 (82.76%) were classified as coagulase positive (CPS) and 10 (17.24%) as coagulase negative (CNS). For the CPS, S. intermedius was more frequent (46.56%), followed by S. aureus (22.42%). Among the CNS, S. warneri was characterized in 13.80% of the strains. The sensitivity of Staphylococcus spp. strains was > 88% for ceftiofur, oxacillin and trimethoprim/sulfamethoxazole ... (Complete abstract click electronic access below)
2

Qualidade microbiológica de águas minerais em garrafas individuais comercializadas em Araraquara

Dias, Maria Fernanda Falcone [UNESP] 22 November 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-11-22Bitstream added on 2014-06-13T20:56:36Z : No. of bitstreams: 1 dias_mff_me_arafcf.pdf: 401309 bytes, checksum: 3615bf97747cd9d854c75ca926044788 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Com a dúvida sobre a qualidade da água de abastecimento público, o cidadão passou a utilizar a água mineral com maior intensidade. Para atender a esta demanda as indústrias aumentaram a produção, novas empresas surgiram e também os falsários. Assim, é necessário conhecer-se a qualidade esperada e paga pelo consumidor nesse produto, realmente existe. O objetivo desta pesquisa foi avaliar aspectos de qualidade microbiológica em amostras de água mineral natural, não carbonatada, em garrafas individuais de 330mL a 600mL, das diversas marcas comercializadas em supermercados na cidade de Araraquara-SP. Foram utilizadas sessenta e nove amostras provenientes de dezessete marcas. As amostras foram adquiridas aleatoriamente, em épocas e estabelecimentos diferentes para que fossem originadas de lotes diversos. Para análise de coliformes totais e coliformes fecais/E. coli utilizou-se a técnica de substratos cromogênicos; para enterococos e Pseudomonas aeruginosa foram utilizadas as técnicas de tubos múltiplos específicas; para contagem de bactérias heterotróficas, foi utilizada a técnica de cultivo em profundidade. Todas as amostras de todas as marcas (100%) apresentaram ausência de coliformes fecais/E.coli, duas amostras (2,9%) de uma marca (5,9%) apresentaram contaminação por coliformes totais, duas amostras (2,9%), de duas marcas (11,8%) apresentaram contaminação por enterococos, três amostras (4,3%) de duas marcas (11,8%) apresentaram Pseudomonas aeruginosa e quarenta amostras (58%) de doze marcas (70,6%) apresentaram contagens acima de 500 UFC/mL para bactérias heterotróficas. Verificou-se que, das sessenta e nove amostras analisadas (100%) apenas seis (8,7%) apresentaram-se contaminadas com um ou mais dos indicadores especificados pela legislação brasileira para águas minerais. Entretanto, considerando os padrões para água mineral e o padrão... / With the doubt on the water quality in public supplying, the citizen started to use the mineral water with larger intensity. For attend this demand the factory had increased the production, new companies had appeared and also the falsifiers. Thus, it’s necessary to know if the quality waited and paid for the consumer in this product, really exists. The objective of the research was to evaluate aspects of microbiological quality in natural mineral water samples, not carbonated, in individual bottles of 330mL to 600mL, of the diverse marks commercialized in supermarkets in the city of Araraquara-SP. Sixty nine samples proceeding from seventeen marks had been used. The samples had been acquired aleatory, at different times and establishments for that they were originated from diverse lots. For analysis of fecal coliform/E. coli and total used it cromogenic substrate technique; for enterococcus and for Pseudomonas aeruginosa was used the technique of multiple tube specific; for counting of heterotrophic bacteria, was used the technique of culture in depth. All the samples of all the marks (100%) had presented absence for fecal coliform/E.coli., two samples (2.9%) of one mark (5.9%) had presented contamination for total coliform, two samples (2.9%), of two marks (11.8%) had presented contamination for enterococcus, three samples (4.3%) of two marks (11.8%) had presented Pseudomonas aeruginosa, and forty samples (58%) of twelve marks (70.6%) had presented counting above of 500 CFU/mL for heterotrophic bacteria. It was verified that, of the sixty nine analyzed samples (100%), only six (8.7%) had been presented contaminated with one or more than the pointers specified for the Brazilian legislation for mineral waters used in this research. However, considering the standards for mineral water and the standard for heterotrophic bacteria established by the legislation for water of human consumption...(Complete abstract click electronic access below)
3

Determination of the quality of environmental water using GC-MS based faecal sterol analysis / Chantel Swanepoel

Swanepoel, Chantel January 2014 (has links)
Faecal indicator bacteria have traditionally been used in the detection of faecal pollution in water, but due to concerns about the lack of reliability of these indicators, alternative methods have been developed. One of which is the detection of sterols present in human and animal excreta via GC-MS analysis of water in this study. The Szűcs method was used to detect six target sterols (coprostanol, cholesterol, dehydrocholesterol, stigmasterol, β-sitosterol, and stigmastanol) in environmental water samples. An initial study was done by analysing raw sewage and effluent (human faecal sterol biomarkers) and water samples were spiked with excreta from cattle, chickens, horses, pigs, and sheep to determine faecal sterol fingerprints. The method was evaluated for quantitation and differences between the water samples from each species. Following liquid-liquid extraction, silylation and derivatization, samples were analysed by GC-MS. Standard curve assays were linear up to 160ng and the limit for quantification was 20ng. The human faecal sterol biomarker was coprostanol, while herbivore profiles were dominated by terrestrial sterol biomarkers (stigmasterol and stigmastanol). Sterol fingerprints and differences in concentrations of sterols between various animals and between animals and humans occurred, providing the opportunity to determine whether faecal pollution was from humans or from animals. The method proved sensitive enough to evaluate faecal contamination in environmental water. Groundwater was collected from bore-holes and surface water samples were collected from the Baberspan Inland Lake. Physico-chemical parameters analysed indicated that pH for surface water samples was above 6.9. The total dissolved solids (TDS) in groundwater indicated that the water was not suitable for human consumption, but could be used for livestock watering. Surface water electrical conductivity (EC) and inorganic nitrates was too high to be used for irrigational purposes. Nitrates in groundwater were too high to be consumed by humans. In groundwater, the total coliform target water quality range (TWQR) was exceeded at 53% of sites analysed and faecal coliform TWQR were exceeded at 77% sites. Surface water samples complied with TWQR with regards to faecal coliforms for full contact recreational activities and livestock watering. The TWQR for E. coli, with regards to full contact recreational activities, was within a safe range for surface water. Faecal streptococci were found in 85% of groundwater sampling sites. And surface water faecal streptococci counts exceeded the TWQR for full contact recreational activities. There is no TWQR for faecal sterols in water, but concentrations of cholesterol and coprostanol was found at three of the groundwater sites analysed. This indicates faecal contamination from possible animal and human origin. Surface water samples analysed showed that the Harts River water is clean and free of faecal sterols, while the water analysed from the inflow, hotel and outflow, cholesterol eluted, which showed faecal contamination, possibly from animals. Faecal sterol markers could be detected in groundwater and surface water, adding an extra dimension to determining the quality of water systems. An optimization and sensitivity study of the method was done on waste water treatment plant (WWTP) raw sewage and effluent. The WWTP sample analysed form Potchefstroom and Carletonville WWTP yielded all six target sterols in the raw sewage water samples, but no sterols eluted in the effluent samples. The raw sewage water sample taken from the Fochville WWTP yielded all six target sterols as well, however, the effluent yielded an unknown compound as well as cholesterol. An alternative study was done where the effluent sample volume was increased. By increasing the volume of water, one can possibly increase the amount (“load”) of sterols extracted and analysed, resulting in a higher abundance of target sterols. By using the target qualifier ions of the six target sterols, and the GC-TOF/MS software, the target sterols could still be qualitatively determined. Optimal volume for raw sewage is 300 ml water sample as this is enough to yield all 6 target sterols. For optimum water quality monitoring via faecal sterol analysis of effluent and other environmental samples, at least 1L sample volume needs to be collected and analysed. The methods described here can be applied to the analysis of environmental water samples. The technical advantages also make it suitable for routine environmental monitoring of faecal pollution. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
4

Determination of the quality of environmental water using GC-MS based faecal sterol analysis / Chantel Swanepoel

Swanepoel, Chantel January 2014 (has links)
Faecal indicator bacteria have traditionally been used in the detection of faecal pollution in water, but due to concerns about the lack of reliability of these indicators, alternative methods have been developed. One of which is the detection of sterols present in human and animal excreta via GC-MS analysis of water in this study. The Szűcs method was used to detect six target sterols (coprostanol, cholesterol, dehydrocholesterol, stigmasterol, β-sitosterol, and stigmastanol) in environmental water samples. An initial study was done by analysing raw sewage and effluent (human faecal sterol biomarkers) and water samples were spiked with excreta from cattle, chickens, horses, pigs, and sheep to determine faecal sterol fingerprints. The method was evaluated for quantitation and differences between the water samples from each species. Following liquid-liquid extraction, silylation and derivatization, samples were analysed by GC-MS. Standard curve assays were linear up to 160ng and the limit for quantification was 20ng. The human faecal sterol biomarker was coprostanol, while herbivore profiles were dominated by terrestrial sterol biomarkers (stigmasterol and stigmastanol). Sterol fingerprints and differences in concentrations of sterols between various animals and between animals and humans occurred, providing the opportunity to determine whether faecal pollution was from humans or from animals. The method proved sensitive enough to evaluate faecal contamination in environmental water. Groundwater was collected from bore-holes and surface water samples were collected from the Baberspan Inland Lake. Physico-chemical parameters analysed indicated that pH for surface water samples was above 6.9. The total dissolved solids (TDS) in groundwater indicated that the water was not suitable for human consumption, but could be used for livestock watering. Surface water electrical conductivity (EC) and inorganic nitrates was too high to be used for irrigational purposes. Nitrates in groundwater were too high to be consumed by humans. In groundwater, the total coliform target water quality range (TWQR) was exceeded at 53% of sites analysed and faecal coliform TWQR were exceeded at 77% sites. Surface water samples complied with TWQR with regards to faecal coliforms for full contact recreational activities and livestock watering. The TWQR for E. coli, with regards to full contact recreational activities, was within a safe range for surface water. Faecal streptococci were found in 85% of groundwater sampling sites. And surface water faecal streptococci counts exceeded the TWQR for full contact recreational activities. There is no TWQR for faecal sterols in water, but concentrations of cholesterol and coprostanol was found at three of the groundwater sites analysed. This indicates faecal contamination from possible animal and human origin. Surface water samples analysed showed that the Harts River water is clean and free of faecal sterols, while the water analysed from the inflow, hotel and outflow, cholesterol eluted, which showed faecal contamination, possibly from animals. Faecal sterol markers could be detected in groundwater and surface water, adding an extra dimension to determining the quality of water systems. An optimization and sensitivity study of the method was done on waste water treatment plant (WWTP) raw sewage and effluent. The WWTP sample analysed form Potchefstroom and Carletonville WWTP yielded all six target sterols in the raw sewage water samples, but no sterols eluted in the effluent samples. The raw sewage water sample taken from the Fochville WWTP yielded all six target sterols as well, however, the effluent yielded an unknown compound as well as cholesterol. An alternative study was done where the effluent sample volume was increased. By increasing the volume of water, one can possibly increase the amount (“load”) of sterols extracted and analysed, resulting in a higher abundance of target sterols. By using the target qualifier ions of the six target sterols, and the GC-TOF/MS software, the target sterols could still be qualitatively determined. Optimal volume for raw sewage is 300 ml water sample as this is enough to yield all 6 target sterols. For optimum water quality monitoring via faecal sterol analysis of effluent and other environmental samples, at least 1L sample volume needs to be collected and analysed. The methods described here can be applied to the analysis of environmental water samples. The technical advantages also make it suitable for routine environmental monitoring of faecal pollution. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
5

Identifying Sources of Fecal Pollution in Water as Function of Sampling Frequency Under Low and High Stream Flow Conditions

Graves, Alexandria Kristen 24 April 2003 (has links)
Sources of fecal pollution were evaluated as a function of sampling frequency with stream samples from Mill Creek, Montgomery County, VA. Samples were collected monthly for one year, plus weekly for four consecutive weeks during seasonal high flows (March), and seasonal low flows (September-October), plus daily for seven consecutive days within the weekly schedules. Thirty stream samples were collected from each of two sites (60 total) in Mill Creek, and 48 isolates of E. coli per sample (total of 2,880 stream isolates) were classified by source using antibiotic resistance analysis (ARA) and comparing the resulting patterns against a known-source E. coli library (1,158 isolates). The same process was performed with enterococci isolates against an enterococci library (1,182 isolates). The average rate of correct classification (ARCC) for the E. coli library with a three-way split (human, livestock, and wildlife) was 89.0%, and the ARCC of the species-specific E. coli library (cattle, deer, goose, human, misc. wildlife) was 88.9%. The ARCC of the enterococci library with a three-way split was 85.3%, and the ARCC of the species-specific enterococci library was 88.1%. The results did not justify the need for daily or weekly sampling, but indicated that monthly was adequate (quarterly and every-other-month were not). There was a seasonal effect as the human signature was highest during high flow while the livestock signature dominated during low flow. The results also indicated that sampling should be done over a period of time that includes both seasonal wettest and driest periods (at least 8 months). / Ph. D.
6

Determining Sources of Fecal Pollution in Water for a Rural Virginia Community

Graves, Alexandria Kristen 15 August 2000 (has links)
This project involves developing and applying bacterial source tracking (BST) methodology to determine sources of fecal pollution in water for a rural community (Millwood, VA). Antibiotic resistance analysis (ARA) is the primary BST method for fecal source identification, followed by randomly amplified polymorphic DNA (RAPD) analysis for confirmation. Millwood consists of 66 homes, all served by individual septic systems, and a stream (Spout Run) passes through the center of the community. Spout Run drains a 5,800 ha karst topography watershed that includes large populations of livestock and wildlife. Stream and well samples were collected monthly and analyzed for fecal coliforms and fecal streptococci, starting in 5/99 and ending in 5/00. Twelve percent of the well samples and 92% of the stream samples were positive for fecal coliforms, and 26% of the stream samples exceeded the recreational water standard (1,000 fecal coliforms/100 ml). ARA of fecal streptococci recovered from the stream samples indicated that isolates of human origin appeared throughout the stream as the stream passed through Millwood with a yearly average of (approx. 10% human, 30% wildlife, and 63% livestock), and the percent human origin isolates declined downstream from Millwood. These results were obtained by comparing the antibiotic resistance profiles of stream isolates against a library of 1,174 known source isolates with correct classification rates of 94.6% for human isolates, 93.7% for livestock isolates, and 87.8% for wildlife isolates. There is a human signature in Spout Run, but it is small compared to the proportion of isolates from livestock and wildlife. The sporadic instances where well water samples were positive appeared primarily during very dry periods. Restricting livestock access to streams can dramatically lower fecal coliform counts during the unusually hot and dry periods. Reducing FC counts to below recreational water standards for Virginia (1000 per 100ml for any one sample) may be achievable, however to maintain streams below standards may prove to be difficult, as Spout Run is in an area where there are large populations of Canada geese, deer, and other wildlife, and will be hard to restrict these animals. / Master of Science
7

Determining the association between household drinking water handling practices and bacteriological quality of drinking water at the point-of-use in the rural communities of Murewa district, Zimbabwe

Rameck, Makokove January 2018 (has links)
Magister Public Health - MPH / There is growing awareness that drinking water can become contaminated following its collection from safe communal sources such as boreholes, as well as during transportation and storage in the house. Drinking water is the most important source of gastroentric diseases worldwide, mainly due to post collection contamination of drinking water. Globally, waterborne diseases are a major public health problem, causing millions of deaths annually. Aim: To determine the association between household drinking water handling practices and bacteriological quality of drinking water at the point-of-use in the rural communities of Murewa district in Zimbabwe.
8

Qualidade bacteriológica de águas de irrigação de hortas nos municípios Araraquara, Boa Esperança do Sul e Ibitinga, SP

Beraldo, Rosa Maria [UNESP] 15 December 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-12-15Bitstream added on 2014-06-13T20:11:00Z : No. of bitstreams: 1 beraldo_rm_me_arafcf.pdf: 282816 bytes, checksum: 5801e8fb514fd0197781c52154b68859 (MD5) / Universidade Estadual Paulista (UNESP) / O consumo de alimentos frescos como frutas e hortaliças representa riscos à saúde humana, uma vez que tais alimentos podem estar contaminados, constituindo veículos de transmissão de várias doenças. A água utilizada na irrigação de hortas representa umas das possíveis fontes desse tipo de contaminação, comprometendo a qualidade do produto e, principalmente, a saúde humana. Assim, o controle da qualidade bacteriológica de águas utilizadas para tal finalidade torna-se de vital importância para a saúde pública. O objetivo deste trabalho foi avaliar a qualidade bacteriológica de amostras de águas utilizadas na irrigação de 40 hortas dos municípios de Araraquara, Boa Esperança do Sul e Ibitinga, SP. Foram colhidas em cada horta duas amostras de águas destinadas à irrigação. Tais amostras foram colhidas no mesmo ponto e em diferentes meses, caracterizando dois grupos de coleta com 40 amostras cada, totalizando 80 amostras. Foi determinado o número mais provável (NMP/100 mL) de coliformes totais, coliformes termotolerantes e enterococos, através da técnica dos tubos múltiplos (APHA, 2005). Foi utilizado o padrão de qualidade estabelecido pela Resolução n°357 do Conselho Nacional do Meio Ambiente- CONAMA, que determina um limite de 200 coliformes termotolerantes em 100 mL de amostra de água utilizada para irrigação de hortaliças consumidas cruas (CONAMA, 2005). Após a análise das amostras referentes à primeira coleta, os proprietários das hortas, cujas águas utilizadas na irrigação não atenderam ao padrão de qualidade estabelecido pela Resolução CONAMA n°357 foram orientados quanto à necessidade de medidas de desinfecção das mesmas ou suas fontes. A segunda coleta das amostras ocorreu somente após terem sido tomadas as providências para a melhoria da qualidade da água, nos casos em que isso foi necessário. Após a primeira análise observou-se... / The consumption of fresh foods such as fruits and vegetables represents risks to human health, since these foods may be contaminated, behaving as sources of various diseases. The water used for irrigation of vegetables gardens represents one of the possible sources of contamination, which may compromise the quality of the product and, mainly, the human health. Thus, the bacteriological quality control of water used for such purposes becomes vitally important for public health. The objective of this paper was to evaluate the bacteriological quality of water used for irrigation of 40 vegetables gardens in the municipalities of Araraquara, Boa Esperança do Sul and Ibitinga, SP. Were collected in each vegetables garden two samples of water for irrigation. The samples were collected in different months at the same point, featuring two groups collection with 40 samples each, totaling 80 samples. It was determined the most probable number (MPN/100 mL) of total coliforms, termotolerants coliforms and enterococcus using the multiple tube technique (APHA, 2005). It was used the quality standard established by Resolution n°357 of Environmental National Council - CONAMA, which determines a limit of 200 termotolerants coliforms in 100 mL of sample of water used for irrigation of vegetables consumed raw (CONAMA, 2005). After the analysis of the samples from the first collects, the owners of the vegetables gardens, whose waters used in irrigation not satisfy the quality standard established by CONAMA Resolution n°357, were instructed about the necessary disinfection measures of the water or its sources. The second collects of the samples occurred only after been taken steps to improve water quality, when it was necessary. After the first analysis it was observed the presence of termotolerants coliforms, in quantities above the permitted by law, in nine samples (22,5%). The owners of these vegetable... (Complete abstract click electronic access below)
9

Indicadores de qualidade, pesquisa de marcadores de virulência e multirresistência aos antimicrobianos em estirpes de Staphylococcus spp. em leite de origem bovina produzido no sistema orgânico /

Siqueira, Amanda Keller. January 2011 (has links)
Resumo: O presente estudo investigou a qualidade microbiológica do leite de duas pequenas propriedades orgânicas (I e II) do estado de São Paulo, bem como a presença de marcadores de virulência de Staphylococcus spp. e isolados bacterianos multirresistentes aos antimicrobianos. Foram analisados os principais constituintes do leite, contagem bacteriana total, nível de celularidade, além da presença de resíduos de antimicrobianos, com base nas Normativas 051 e 064 do MAPA. O efeito das estações do ano sobre os parâmetros pesquisados também foi considerado. Foram realizadas 12 colheitas em cada uma das duas propriedades, das quais 12 mensais dos latões e quatro trimestrais de todos os animais. No total foram colhidas amostras de leite de 178 animais (259 tetos). Destes, 125/259 (48,27%) tetos acusaram mastite subclínica no CMT, 2/259 (0,77%) tetos mastite clínica e 132/259 (50,96%) foram negativos. A mediana da CCS das duas propriedades variou entre 311,67 x 1000 céls/mL e 447,83 x 1000 céls/mL e a CBT variou entre 25,4 x 1000 UFC/mL e 141,63 x 1000 UFC/mL, sem influência das estações do ano. Os principais constituintes do leite mantiveram-se dentro dos parâmetros estabelecidos. Das 86 amostras de leite da propriedade I, seis (6,97%) foram positivas para a presença de resíduos de antimicrobianos, enquanto das 173 amostras da propriedade II, 16 (9,24%) foram positivas. Staphylococcus spp. e Corynebacterium bovis foram os micro-organismos mais freqüentes, isolados em 58/259 (22,39%) e 50/259 (19,30%), respectivamente, de amostras de leite dos animais. Das 58 linhagens de Staphylococcus spp., 48 (82,76%) foram classificadas como coagulase positivas (ECPs) e 10 (17,24%) como coagulase negativas (ECNs). Para os ECPs, S. intermedius foi mais frequente (46,56%), seguido por S. aureus (22,42%). Dentre os ECNs, S. warneri foi caracterizado em 13,80% das linhagens. A sensibilidade das ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present study investigated the microbiological quality of milk from two small organic properties (I and II) from São Paulo State, as well as the presence of virulence markers of Staphylococcus spp. and multidrug-resistant isolates to antimicrobials. We analyzed the major milk components, total bacterial count, level of cellularity and the presence of antimicrobial residues, based on Normative 051 and 064 MAPA, Brazil. The effect of seasons on the studied parameters was also considered. Twenty harvests were conducted in each of the two properties, including 12 monthly and four quarterly samples of all animals. In total we collected milk samples from 178 animals (259 mammary glands). Of these, 125/259 (48.27%) mammary glands showed subclinical mastitis on CMT, 2/259 (0.77%) clinical mastitis and 132/259 (50.96%) had been negative. The median of SCC of the two properties varied between 311.67 x 1000 cells/mL and 447.83 x 1000 cells/mL and TBC showed between 25.4 x 1000 CFU/mL and 141.63 x 1000 CFU/mL, without influence of the seasons. The contents of the main milk components remained with the established standards. Of the 86 samples of milk from the property I, six (6.97%) were positive for the presence of antimicrobial residues, while from 173 samples of property II, 16 (9.24%) were positive. Staphylococcus spp. and Corynebacterium bovis were the most frequent microorganisms isolated in 58/259 (22.39%) and 50/259 (19.30%), respectively, in the milk samples of animals. Of the 58 strains of Staphylococcus spp., 48 (82.76%) were classified as coagulase positive (CPS) and 10 (17.24%) as coagulase negative (CNS). For the CPS, S. intermedius was more frequent (46.56%), followed by S. aureus (22.42%). Among the CNS, S. warneri was characterized in 13.80% of the strains. The sensitivity of Staphylococcus spp. strains was > 88% for ceftiofur, oxacillin and trimethoprim/sulfamethoxazole ... (Complete abstract click electronic access below) / Orientador: Márcio Garcia Ribeiro / Coorientador: Domingos da Silva Leite / Banca: José Paes de Almeida Nogueira Pinto / Banca: Maria de Lourdes Ribeiro de Souza da Cunha / Banca: Evelise Oliveira Telles / Banca: Elizabeth Oliveira da Costa Freitas Guimarães / Doutor
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Water quality improvement and plant root function in an ecological system treating dairy wastewater

Morgan, Jennifer Anne 30 July 2007 (has links)
No description available.

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