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1
Hector, D. A. "Studies on the acid preservation of poultry byproducts." Thesis, University of Nottingham, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334883.
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Hughes, Claire Helen. "Influence of ionising radiation on the microflora of poultry meat." Thesis, Queen's University Belfast, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334566.
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Al-Haddad, Khawla S. "Aspects of the behaviour of Salmonella spp. associated with poultry." Thesis, University of Reading, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288686.
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Wang, Zihua. "Persistence of ESBL E. coli in Poultry Production Free of Antibiotic Application." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1524047763189613.
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Fonseka, Thithalapitige Sunil Gamini. "Molecular typing of food poisoning bacteria isolated from farm shrimp and poultry." Thesis, University of Nottingham, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316950.
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Mabogo, Rudzani David Lesly. "The prevalence and survival of Campylobacter, Salmonella and Listeria species in poultry processing plant." Thesis, University of the Western Cape, 2004. http://etd.uwc.ac.za/index.php?module=etd&.
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The organisms in this study were chosen due to their associations with foods and their potential as food borne pathogens. Food borne diseases are an import public health problem in most countries. Bacteria of the genera Campylobacter, Salmonella and Listeria can be transported by poultry and poultry products to humans. Gastroenteritis, typhoid fever, diarrhea, dysentery may originate from the infection. This study was undertaken to determine the incidence of pathogens in a poultry processing plant using polymerase chain reaction and conventional tests and to determine the formation and survival of biofilm cells of food pathogens in trisodium phosphate.
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Brena, Maria Camilla. "Effect of different poultry production methods on Campylobacter incidence and transmission in the broiler meat food chain." Thesis, University of Liverpool, 2013. http://livrepository.liverpool.ac.uk/18837/.
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Campylobacter is the main cause of human bacterial gastroenteritis worldwide. Within the EU reported cases are rising each year. Epidemiological studies have identified that chicken meat is one of the major sources of human infection. However, it is poorly understood whether differences in chickens’ rearing and production methods impact on the contamination levels of Campylobacter on chicken meat and therefore the risk of entry into the food chain. To investigate the role of production system, flocks from diverse broiler commercial production systems with differences in welfare standards, bird type and stocking densities were investigated during the whole rearing period and at slaughter. Caecal samples were collected to estimate the flock prevalence. In order to assess the level of carcass contamination during processing, neck skin samples were collected at different production stages. Breast meat samples were also investigated to estimate the risk that chicken meat poses to human health. The objective was to link the flock Campylobacter status to the risk of contamination on the consumer’s plate. All samples were cultured for the presence of Campylobacter species. A quantitative method based on ISO 10272-2:2006, was used to determine the level of flock colonisation and Campylobacter contamination on broiler carcasses and final products. Results show that birds reared indoors under higher welfare standards with decreased stocking density with a slower growing breed (Hubbard JA57) had a reduced prevalence of Campylobacter, compared to the standard fast growing breed (Ross 308) when grown at the same stocking density. The production system with the higher Campylobacter prevalence and the higher Campylobacter count in the caecal contents, also reported a greater Campylobacter prevalence and counts on carcasses. The bacterial numbers on the final product appeared to be strongly associated with the intestinal colonisation of the slaughter batch. Consequently it is crucial to prevent flock colonisation during the rearing period, to ensure negative flocks are entering into the processing plant. The significance of the aforementioned point was also highlighted by the fact that production stages such as final washing and chilling have little impact in the reduction of contamination of the final product. The high level of contaminated carcasses showed clearly that the chicken meat is putting the UK consumers’ health at risk. An increased incidence of welfare issues, such as pododermatitis and hock lesions, was observed among the production system with the higher level of colonisation, which bring to light a link between Campylobacter colonisation and welfare issues. Furthermore, this study emphasised that stressful events such as thinning and transport were followed by an increase in Campylobacter prevalence. This highlights the importance of animal health and welfare interactions with Campylobacter spp colonisation. Multi Locus Sequence Typing (MLST) was used to determine how diverse and distinct the genetic Campylobacter population structure was among the different commercial production systems investigated. Results showed that all production systems could be potential sources of Campylobacter infection in humans with common clonal complexes found. Changes in the prevalence of genotypes associated with the final product compared to those genotypes found in birds arriving from farms were observed. This may reflect the enhanced ability of certain genotypes to resist environmental stressors, such as carcass washing, chilling, chlorine dioxide treatment and oxygen that occur during processing. In this data set, isolates belonging to the ST-257 complex showed a higher tendency to survive in the slaughterhouse environment. Internal contamination of the breast muscle was also reported in our study, hence posing a further public health threat, as the bacteria contained within the muscle are better able to survive cooking. These studies have demonstrated that this pathogen was highly prevalent among the broiler population investigated. Due to the common extent of this pathogen in food and its impact on human health, it is necessary for the Government bodies, food producers and retailers, to raise consumers’ awareness of the Campylobacter issue. Particularly the consumers must be made aware of how to manage the risk appropriately during food preparation.
8
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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Kaufman, Irene Jennifer. "The Recovery of Protein from Egg Yolk Protein Extraction Granule Byproduct." DigitalCommons@CalPoly, 2017. https://digitalcommons.calpoly.edu/theses/1738.
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In addition to proving an excellent source of nutrients, eggs are used in the food, cosmetic, and biotechnology industries for their rheological and bioactive properties. Much of the potential for the added value is in individual components of the egg, rather than the whole egg. At low speed centrifugation, yolk separates into two distinct fractions—granules and plasma. It is becoming increasingly popular in the industry to remove the plasma fraction of the egg yolk to use for its livetins, particularly immunoglobulin Y, leaving behind a granule by-product (“yellow cake”). Previous research has shown potential added-value from the granule fraction, especially from its phosvitin and phospholipids. Granules are protein aggregates with complexes of phosvitin and high density lipoproteins linked by phosphocalcic bridges. In their native form, the proteins are mostly insoluble, however previous studies have shown the links can be broken by alterations in pH, ionic strength, and mechanical treatments. This thesis project seeks to find potential uses for the egg yolk by product after the removal of the livetin fraction by means of further fractionation with mechanical treatment (filtration). Two variables were tested to extract more proteins from the yellow cake. Salt was added to 10% solids solution of yellow cake in water before filtration at four different NaCl levels: 0%, .05%, 1%, and 2.5%. Additionally pH was tested at four different levels: 4.6, 4.8, 5.0, 5.2. The samples were also tested for antibacterial properties against Escherichia v coli with a minimum inhibitory concentration assay (MIC). Analysis with BCA showed salt concentration had a significant effect on the yield of protein. The highest concentration of salt tested, 2.5%, had the highest protein yield. Additionally, SDS PAGE showed 2.5% salt had the most unique protein bands. This could be to the disruption of the phosphocalcic links between the phosvitin and HDL by NaCl, allowing the protein to solubilize. pH did not have a significant effect on the yield or types of proteins in the range tested in this experiment. There is no conclusive evidence of antibacterial properties against E. coli from the protein extract. The MIC assay had growth show up in all wells with the protein extract, however there was a visible decrease in turbidity with higher concentration of the protein extract. This could mean that the protein extract does have some antibacterial properties, but needs testing at higher concentrations or with isolated proteins/peptides. The SDS-PAGE revealed bands showing phosvitin present, which has known antibacterial properties. Overall, improvements to the methods for further protein extraction from egg yolk by-products will help lead the industry to finding novel uses and product applications.
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Ribeiro, Maria Luiza Rezende. "Qualidade das carcaças de frango de abatedouros e pontos de venda de Goiás: pesquisa de Campylobacter termotolerantes." Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/7133.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The ingestion of foods contaminated with Campylobacter spp. results in campylobacteriosis in humans. This disease is the main cause of diarrhea in the United States and European Union. The most common reservoirs of this microorganism are chickens and the consumption of their meat, raw or undercooked, is the main source of contamination to humans. The most prevalent species involved in infections are Campylobacter jejuni, Campylobacter coli and Campylobacter lari that can contaminate carcasses during the slaughter and handling of chickens. The aim of this study was to determine the prevalence of thermotolerant Campylobacter in chilled and later frozen chicken carcasses commercialized in the city of Goiânia, Goiás. With the support of the Municipal Sanitary Surveillance Department and the Goiás Agency for Agricultural and Farming Defense, forty cooled and frozen carcasses samples were collected in abattoirs and its retail outlets, from May to September/2015. The microbiological analysis was performed according to the methods of the International Organization for Standardization 10272-1:2006. For molecular identification, the Polymerase Chain Reaction technique was performed to detect the hipO (Campylobacter jejuni) and glyA genes (Campylobacter coli and Campylobacter lari). It was found a contamination prevalence of 17.5 % (n=7) of Campylobacter spp.. Between the 24 samples collected from slaughterhouses, 12.5% (n = 3) were contaminated. Among the 16 collected in points of sale, 25.0% (n = 4) presented positivity for the bacterium. Campylobacter lari was not detected in the evaluated samples. The results show that the bacteria remains viable at all stages of the chicken production chain, representing a risk for outbreaks of gastroenteritis. The presence of bacteria in chicken from market reinforces the need for education of poultry farmers and traders regarding the public health risk that these products represent. Awareness raising is needed to improve management, as well as preventive and corrective measures in the production and marketing of these products. In addition, the prevalence found in the present study reinforces the need to establish legal standards that determine the research of the microorganism in this type of food.
A ingestão de alimentos contaminados por bactérias do gênero Campylobacter resultam em campilobacteriose em humanos. Esta é uma das causas mais comuns de diarreia nos Estados Unidos e União Europeia. Um dos maiores reservatórios deste micro-organismo são produtos avícolas, sendo sua carne, crua ou mal cozida, a principal fonte de contaminação para o homem. As espécies mais prevalentes envolvidas nas infecções são Campylobacter jejuni, Campylobacter coli e Campylobacter lari que podem contaminar as carcaças durante o abate e a manipulação de frangos. O objetivo desse estudo foi determinar a prevalência de Campylobacter termotolerantes em carcaças de frango refrigeradas e posteriormente congeladas comercializadas no município de Goiânia, Goiás. Com o apoio do Departamento de Vigilância Sanitária Municipal e Agência Goiana de Defesa Agropecuária, foram coletadas, entre os meses de maio e setembro de 2015, 40 amostras de carcaças refrigeradas e congeladas em abatedouros em Goiás e seus pontos de venda em Goiânia. A metodologia para isolamento e identificação obedeceu às normas da International Organization for Standardization 10272- 1:2006. Para identificação molecular, foi realizada a técnica da Reação em Cadeia da Polimerase para detecção dos genes hipO (Campylobacter jejuni) e glyA (Campylobacter coli e Campylobacter lari). Foi encontrada prevalência de 17.5 % (n=7) de contaminação de carcaças por Campylobacter spp.. Dentre as 24 amostras coletadas em abatedouros, 12,5 % (n=3) estavam contaminadas. Já entre as 16 coletadas em pontos de venda, 25,0 % (n=4) apresentaram positividade para a bactéria. Não foi detectado Campylobacter lari nas amostras avaliadas. Os resultados evidenciam que a bactéria permanece viável em todas as etapas da cadeia produtiva de frangos, representando um risco para a ocorrência de surtos de gastroenterites. A presença da bactéria em frangos aponta para a necessidade de educação de criadores de aves e comerciantes quanto ao risco à saúde pública que estes produtos representam. É necessária sensibilização para melhorar a gestão, além da realização de medidas preventivas e corretivas no sistema de produção e comercialização destes produtos. Além disso, a prevalência encontrada no presente estudo reforça a necessidade do estabelecimento de padrões legais que determinem a pesquisa do micro-organismo neste tipo de alimento.
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Sigarini, Cleise de Oliveira 1977. "Ocorrência de Listeria monocytogenes em frangos alternativos /." Botucatu : [s.n.], 2009. http://hdl.handle.net/11449/104107.
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Resumo: O Brasil é um dos principais países produtores/exportadores e consumidores de carne de frango no mundo. A maioria das aves é criada tradicionalmente, porém uma parte já é produzida pelo método alternativo que preconiza o bem- estar das aves sem o uso de antibióticos, coccidiostásticos, promotores de crescimento e ração de origem animal. No entanto, devido à ausência de inibidores exógenos, bactérias patogênicas podem se disseminar sem restrição na granja, sendo levadas ao abatedouro, contaminando não só o ambiente de abate, mas também o produto destinado ao consumidor final. Uma destas bactérias, Listeria monocytogenes é um microrganismo ubíquo que provoca a listeriose, doença zoonótica grave que leva a aborto/natimortos, neuropatias, gastroenterites, principalmente em crianças e idosos. É portanto, de fundamental importância que conheçamos a prevalência desta bactéria da recepção das aves no abatedouro até o acondicionamento do produto final, para que possamos orientar com precisão os principais focos de contaminação. Assim, foram colhidas 230 amostras sendo estas, obtidas em ambientes, equipamentos, utensílios e em carcaças de frango em diferentes etapas de abate e processamento de frangos alternativos. As amostras foram analisadas pela técnica convencional de isolamento de L. monocytogenes e posterior confirmação por técnica molecular. De um total de 230 amostras analisadas, 12 foram confirmadas como L. monocytogenes, representando 5,21% do total de amostras colhidas em diferentes pontos do fluxograma de abate. Assim, do total de amostras positivas (12), apenas duas (3,33%) destas foram identificadas no produto final (cortes embalados).Abstract: Brazil is one of the major producers/exporters and consumers of chicken meat in the world. Chicken production has been mainly based on confinement systems, although many animals have been raised in alternative systems, which focuses animal welfare, antibiotic-free animal production, with no coccidiostatic drugs or growth promoters or food of animal origin. However the absence of exogenous inhibitors could potentially spread pathogenic bacteria to the farm and then to the slaughterhouse, contaminating not only the environment of slaughter, but also the final product. One of these bacteria, Listeria monocytogenes, is an ubiquitous pathogen which causes listeriosis, a severe zoonotic disease that leads to abortion/ stillbirth, neuropathy, gastroenteritis, mainly in children and elderly people.Therefore, the identification of sources of this bacterium in poultry slaughterhouses and in the final product is very important. A total of 230 samples were collected from the slaughterhouse environment, equipment, utensils and carcasses in different stages of slaughtering and chicken processing. Samples were analyzed using the conventional technique for isolation of L. monocytogenes. Confirmation was achieved using molecular technique. Only 12 out of 230 samples were positive for L. monocytogenes which represent 5.21% of the samples from this slaughterhouse. Only two samples (3.33%) from the final product were positive for this pathogen.
Orientador: Roberto de Oliveira Roça
Coorientador: José Paes de Almeida Nogueira Pinto
Banca: Hélio Langoni
Banca: Vera Lúcia Moraes Rall
Banca: Ricardo Ichiro Sakate
Banca: João Garcia Caramori Júnior
Doutor
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Sigarini, Cleise de Oliveira [UNESP]. "Ocorrência de Listeria monocytogenes em frangos alternativos." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/104107.
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Universidade Estadual Paulista (UNESP)
O Brasil é um dos principais países produtores/exportadores e consumidores de carne de frango no mundo. A maioria das aves é criada tradicionalmente, porém uma parte já é produzida pelo método alternativo que preconiza o bem- estar das aves sem o uso de antibióticos, coccidiostásticos, promotores de crescimento e ração de origem animal. No entanto, devido à ausência de inibidores exógenos, bactérias patogênicas podem se disseminar sem restrição na granja, sendo levadas ao abatedouro, contaminando não só o ambiente de abate, mas também o produto destinado ao consumidor final. Uma destas bactérias, Listeria monocytogenes é um microrganismo ubíquo que provoca a listeriose, doença zoonótica grave que leva a aborto/natimortos, neuropatias, gastroenterites, principalmente em crianças e idosos. É portanto, de fundamental importância que conheçamos a prevalência desta bactéria da recepção das aves no abatedouro até o acondicionamento do produto final, para que possamos orientar com precisão os principais focos de contaminação. Assim, foram colhidas 230 amostras sendo estas, obtidas em ambientes, equipamentos, utensílios e em carcaças de frango em diferentes etapas de abate e processamento de frangos alternativos. As amostras foram analisadas pela técnica convencional de isolamento de L. monocytogenes e posterior confirmação por técnica molecular. De um total de 230 amostras analisadas, 12 foram confirmadas como L. monocytogenes, representando 5,21% do total de amostras colhidas em diferentes pontos do fluxograma de abate. Assim, do total de amostras positivas (12), apenas duas (3,33%) destas foram identificadas no produto final (cortes embalados).
Brazil is one of the major producers/exporters and consumers of chicken meat in the world. Chicken production has been mainly based on confinement systems, although many animals have been raised in alternative systems, which focuses animal welfare, antibiotic-free animal production, with no coccidiostatic drugs or growth promoters or food of animal origin. However the absence of exogenous inhibitors could potentially spread pathogenic bacteria to the farm and then to the slaughterhouse, contaminating not only the environment of slaughter, but also the final product. One of these bacteria, Listeria monocytogenes, is an ubiquitous pathogen which causes listeriosis, a severe zoonotic disease that leads to abortion/ stillbirth, neuropathy, gastroenteritis, mainly in children and elderly people.Therefore, the identification of sources of this bacterium in poultry slaughterhouses and in the final product is very important. A total of 230 samples were collected from the slaughterhouse environment, equipment, utensils and carcasses in different stages of slaughtering and chicken processing. Samples were analyzed using the conventional technique for isolation of L. monocytogenes. Confirmation was achieved using molecular technique. Only 12 out of 230 samples were positive for L. monocytogenes which represent 5.21% of the samples from this slaughterhouse. Only two samples (3.33%) from the final product were positive for this pathogen.
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Rodriguez-Palacios, Alexander. "Ecology and Epidemiology of Human Pathogen Clostridium difficile in Foods, Food Animals and Wildlife." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1313582304.
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Viliani, Samira, and Samira Viliani. ""EVALUATION OF CHILLING EFFICIENCY, MEAT TENDERNESS, AND MICROBIAL ANALYSIS OF BROILER CARCASSES USING SUB-ZERO SALINE SOLUTIONS"." DigitalCommons@CalPoly, 2019. https://digitalcommons.calpoly.edu/theses/2091.
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The poultry industry is seeking an advanced chilling system that can improve chilling efficiency, microbial safety, and water consumption without compromising meat quality. The objective of this study was to evaluate the effects of sub-zero saline chilling methods on chilling efficiency, breast fillet tenderness and microbial reduction of broiler carcasses. Following evisceration and rinsing, broiler carcasses were randomly assigned to one of three chilling solutions: 1) 0% salt or ice water control (0% NaCl/0.5oC), 2) 3% salt (3% NaCl/-1.8oC), and 3) 4% salt (4% NaCl/-2.41oC) solutions. Broiler carcasses in sub-zero saline solutions reached the target internal temperature of < 4.4 oC in a faster rate than the 0% salt control, reducing the chilling time by 11% and 39 % for 3% NaCl/-1.8oC and 4% NaCl/-2.41oC solutions, respectively. There was no significant difference in breast fillet pH, regardless of chilling treatment (P < 0.05). However, the breast fillets from sub-zero saline solutions showed higher R-value and longer sarcomere length than those of control fillets (P < 0.05). Breast fillets excised from carcasses in 4% NaCl/2.41oC were significantly tenderized more than the control fillets, with an intermediate tenderness observed for the fillets from 3% NaCl/-1.8oC (P< 0.05). Before chilling, broiler carcasses contained mesophilic aerobic bacteria (MAB), Escherichia coli(E. coli), and total coliforms for 3.81, 0.78, and 1.86 log colony forming unit (CFU)/g, respectively. After chilling, the populations of E. coliand total coliforms were significantly reduced on the carcasses in 3% NaCl/-1.8oC and 4% NaCl/-2.41oCcompared to the control fillets (P< 0.05). There was no significant difference for MAB populations, regardless of treatment. Based on these results, chilling of broiler carcasses in 4% NaCl/-2.4 °C solution seems to be the best choice to improve chilling efficiency, meat tenderness, and microbial reduction compared to the control (0% NaCl/0.5ºC) and 3% NaCl/-1.8oCsolutions.
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Rosa, Sarah Inês Rodrigues. "Isolamento e identificação de Campylobacter spp. em linguiças de frango frescal." Universidade Federal de Goiás, 2015. http://repositorio.bc.ufg.br/tede/handle/tede/5142.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Campylobacteriosis have been related as main cause of gastroenteric diseases in Europe and North America. In Brazil, the lack of data about this disease hinders a comparison with other countries and difficult the decision making to combat the causative bacterium. Due high incidence of Campylobacter spp. in meat, main in poultry carcasses and by-products, this study aimed isolate and identify this bacteria in chicken fresh sausage sampled in Aparecida de Goiânia, in Goiás state. Thirty-four samples were collected in the period from July to October, each one were subdivided in 68 sub-samples, half of sub-samples were analyzed immediately, in fresh/chilled condition, and the other half were frozen for further analysis. In 11.65% of fresh samples were isolated Campylobacter coli and Campylobacter lari. For the frozen samples, no positive results were observed. Worked also with simple and double concentration of enrichment medium, recovering three positive samples in the simple one and a positive sample in the double. It was observed 100% resistance against the antimicrobial bases tested. It is recommended more studies of this nature, broadening the scope as to poultry products and greater number of samples; therefore, it is believed that they may evaluated the prevalence of this important microorganism in animal products in the Goiás state. Such investigations may provide important information for the National Program for Monitoring Prevalence and Bacterial Resistance in Chicken, established in 2008 by the National Agency of Sanitary Surveillance of the Ministry of Health.
Campilobacteriose tem sido frequentemente relatada como principal causadora de doenças gastroentéricas na Europa e América do Norte. No Brasil, a escassez de dados em relação à notificação dessa enfermidade dificulta uma comparação com outros países e a tomada de decisões quanto a políticas de combate à bactéria causadora. Devido a relatos de alta incidência de Campylobacter spp. em carnes, principalmente em carcaças de frango e derivados, este estudo teve como objetivo o isolamento e identificação dessa bactéria em linguiças de frango do tipo frescal obtidas no município de Aparecida de Goiânia, no estado de Goiás. Foram coletadas 34 amostras do produto no período de julho a outubro de 2014, cada uma delas foi dividida em duas partes totalizado 68 subamostras, metade delas foram imediatamente analisadas, na condição fresca/refrigerada, e metade foi submetida ao congelamento para posterior análise. Em 11,75% das amostras frescas pesquisadas, isolou-se Campylobacter coli e Campylobacter lari. Não foi observado resultado positivo para Campylobacter spp. nas linguiças congeladas. Trabalhou-se também, com simples e dupla concentração do meio de enriquecimento, recuperando três amostras positivas no meio simples e uma amostra positiva no meio em dupla concentração. Foi observada 100% de resistência frente às bases antibióticas testadas. Recomenda-se mais estudos desta natureza, ampliando a abrangência quanto aos produtos avícolas e com maior número de amostras, pois acredita-se que poderão avaliar a prevalência deste importante micro-organismo em produtos de origem animal no estado de Goiás. Tais investigações poderão contribuir com informações importantes para o Programa Nacional de Monitoramento da Prevalência e da Resistência Bacteriana em Frango, estabelecido em 2008 pela Agência Nacional de Vigilância Sanitária do Ministério da Saúde.
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Andrigheto, Cristiano. "Disseminação de Salmonella Enteritidis isoladas em uma cadeia produtiva industrial avícola: determinação do perfil de resistência a antimicrobianos e caracterização genotípica." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-25072017-152730/.
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Salmonella é um dos principais agentes de enfermidades transmitidas por alimentos em diversos países, sendo a carne de frango um dos principais veículos envolvidos em surtos. O Brasil vem se destacando como um dos maiores exportadores mundiais deste alimento. O ambiente de criação das aves é apontado como um importante foco de infecção das aves e o ambiente industrial de abate e processamento é importante na disseminação deste ·microrganismo. Na busca pela produção de alimentos seguros do ponto de vista microbiológico, uma das ferramentas utilizadas é a subtipagem de microrganismos isolados ao longo da cadeia de produção, que permite determinar rotas de contaminação do produto final. Os objetivos deste trabalho são: o estudo da disseminação dos subtipos de Salmonella Enteritidis nas várias etapas de uma cadeia de produção industrial de carne de frango, empregando-se diversos métodos de subtipagem e a determinação da resistência a antimicrobianos destas cepas. 108 isolados de Salmonella Enteritidis dos fagotipos PT1, PT4 e PT7a foram obtidos nos anos de 2002 e 2003, a partir de amostras ambientais e de frango relativas a sete sub-regiões de uma cadeia produtiva industrial avícola. Os perfis de resistência destes isolados foram determinados frente a antimicrobianos de uso humano e veterinário e eles foram submetidos a subtipagem por PFGE, RAPO, ribotipagem e PCR-ribotipagem. Foram detectados 21 perfis de resistência diferentes, com 6,5% das cepas sensíveis a todas as drogas, 33,3% resistentes a um ou dois antimicrobianos e 83,3% apresentando resistência intermediária a até quatro deles. Os níveis relativamente elevados de resistência são preocupantes e a diminuição da pressão seletiva deve ser um objetivo para os produtores de aves. De modo geral, a subtipagem permitiu separar as cepas em 13 genótipos, com elevada similaridade entre si. Porém, a maior parte das cepas (69,4%) pertenceu a apenas três deles, que foram encontrados ao longo de toda a cadeia produtiva. A ribotipagem foi o método que apresentou o melhor poder discriminatório (D = 0,701), porém nem todas as cepas foram tipáveis por este método. Não foram encontradas correlações entre os perfis de resistência a antimicrobianos e fagotipos, nem entre genótipos e fagotipos. Porém, dois genótipos proximamente correlacionados e predominantemente encontrados em uma sub-região reuniram apenas cepas com resistência intermediária ou resistentes exclusivamente à furazolidona. A similaridade elevada entre os genótipos evidencia a origem clonal das cepas.Salmonella is one of the most important foodborne disease agents all over the world, and chicken is recognized as an important vehicle of the infection. Chicken production in Brazil has increased in the last couple of years and the country is now ranked 2nd as producer/exporter of this commodity. For this reason there is an increased concern over the safety of these goods. This study deals with the dissemination, antimicrobial resistance, and genetic characterization of S. Enteritidis strains isolated from an industrial chicken production chain. 108 isolates, phagetypes PT1, PT4 and PT7a, were obtained at different steps of the commercial production from farm to frozen cuts, and the broilers were from different producers supplying the same processing plant. Tests for susceptibility to 12 human and veterinary antimicrobial agents were performed. The strains were also typed by PFGE, RAPO, ribotyping, and PCR-ribotyping. 6.5% of the strains were susceptible to the 12 drugs tested and 33.3% were resistant to 1 or 2 of them. Intermediate resistance to up to 4 agents was observed in 83.3% of the isolates. Combining all the typing methods allowed the division of the strains in 13 genotypes with elevated degree of similarity. However, 69.4% of the strains belonged to 3 main phagetypes spread along the production chain. There was no correlation between phagetypes and genotypes, or phagetypes and resistance profiles. However, most strains from one sub-region were from 2 genotypes and showed intermediate resistance to, or were resistant to furazolidone. The high degree of similarity amongst the genotypes indicates the clonal origin of the strains. The relatively high resistance to antimicrobial agents is a cause of concern and trying to diminish the selective pressure has to be a goal for broiler producers.
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Dias, Denise de Almeida Marques. "Persistência de cepas de Listeria monocytogenes em linha de abate industrial de frango em um matadouro localizado no Estado de São Paulo." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-07042010-155128/.
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Listeria monocytogenes é um microrganismo conhecido como causador de enfermidades transmitidas por alimentos desde a década de 80 quando foram descritos surtos de listeriose ocorridos na América do Norte e Europa. Dentre os alimentos de origem animal que veiculam esse patógeno, as aves e seus produtos têm merecido atenção especial por parte de alguns pesquisadores devido à associação feita entre aves e uma possível contaminação durante o processamento, acarretando a contaminação dos produtos finais. Os objetivos desta pesquisa foram avaliar a ocorrência de L. monocytogenes em diferentes etapas da produção de carcaça de frango em um matadouro frigorífico situado no Estado de São Paulo; avaliar a diversidade genética e sorológica das cepas de L. monocytogenes isoladas; correlacionar a diversidade genética das cepas isoladas com a distribuição nas diferentes etapas da linha de processamento, avaliar a persistência das cepas isoladas nesse matadouro e comparar os perfis genéticos de cepas de L. monocytogenes obtidos em nosso país com aqueles obtidos em um matadouro de aves com capacidade similar na Espanha. Foram realizadas 4 amostragens nos meses de julho e novembro de 2005, e março e maio de 2006 em um matadouro situado no Estado de São Paulo. Foi examinado um total de 178 amostras de carcaças de frango, pele de pescoço e de superfícies de contato e superfícies sem contato com o alimento. Os isolados foram submetidos à caracterização de sorogrupos por Reação de Polimerização em Cadeia (multiplex PCR) e à subtipagem por Eletroforese em Gel de Campo Pulsado (PFGE). Das 178 amostras analisadas, 28 (15,7%) foram positivas para L. Monocytogenes. Dentre as amostras positivas, 12 (42,9%) foram oriundas de superfícies sem contato com o produto, 9 (32,1%) de superfícies de contato com o produto e 7 (25%) da carcaça inteira de frango, não sendo detectada L. monocytogenes em pele de pescoço de frango. Dos 41 isolados de L. monocytogenes avaliados, 11 (26,8%) pertencem ao grupo 1 (1/2a ou 3a), 5 (12,2%) ao grupo 3 (1/2b, 3b ou 7) e vinte e cinco (61%) ao grupo 4 (4b, 4d ou 4e). A análise por PFGE forneceu 9 pulsotipos AscI, 6 ApaI e 14 perfis combinados, caracterizando quatro grupos clonais. Estes grupos clonais estavam amplamente disseminados ao longo das etapas de processamento. Quando comparado com dados de estudo prévio realizado no mesmo matadouro, verifica-se a existência de cepas persistentes de L. monocytogenes no ambiente. A comparação entre os pulsotipos de L. monocytogenes isolados no Brasil e aqueles da Espanha mostrou que não há correlação genética entre as cepas, sendo gerado dos grupos distintos. Isto é uma indicação de que o comércio de carcaças de frango entre os dois países não está ocasionando a disseminação de L. monocytogenes no país importador.Listeria monocytogenes is a well-known microorganism as cause of foodborne illness since the occurrence of the first outbreak in 1980. Among foods of animal origin that serve as vehicle of this pathogen, poultry and their products are receiving special attention due to their association with outbreaks. The aims of this research were to evaluate the occurrence of L. monocytogenes in different steps of production of chicken carcasses in an abattoir in São Paulo state; to evaluate the genetic and serological diversity of L. monocytogenes isolates; to correlate the isolates with their distribution along processing line and to evaluate the persistence of strains of L. monocytogenes in the environment and evaluate the occurrence of L. monocytogenes in different steps of production of chicken carcasses in an abattoir in Brazil and at genetically correlate our data with the ones obtained in an equivalent abattoir in Spain. Samples were collected in July and November 2005, and March and May 2006. A total of 178 samples comprising chicken carcasses, neck skin, surfaces that enter in contact with the product and surfaces that not enter in contact with product were analysed. The isolates were submitted to characterization of serogroup through multiplex PCR and subtyping using PFGE. Among 178 samples, 28 (15.7%) were positive for L. monocytogenes: 12 (42.9%) were from the surfaces that do not enter in contact with the product, 9 (32.1%) from the surfaces that enter in contact with the product and 7 (25%) from the carcasses samples. No L. monocytogenes was detected among the neck skin samples. The 41 isolates were classified as group 1 [11 (26.8%)]; group 3 [5 (12.2%)] and group 4 [25 (61%)]. The molecular typing by PFGE resulted in 9 AscI and 6 ApaI profiles, and 14 composite profiles, resulting in four clonal groups. These clonal groups were spread throughout the processing line. When these results were compared with the results obtained in a previous study, persistent strains could be observed. The comparison between pulsotypes of L. monocytogenes isolated in Brazil and those isolated in Spain showed that there is no genetic correlation between strains. Two distinct clonal groups were obtained. This results indicates that chicken carcasses trade between Brazil and Spain is not disseminating L. monocytogenes in the importer country.
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Marcenovicz, Priscila Cavalheiro. "Avaliação da influência da etapa de salga do abate Shechita na população de Staphylococcus aureus em carcaças de frango -- caracterização feno e genotípica dos isolados." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-10092012-133644/.
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O abate Shechita de aves, diferentemente do abate convencional, realiza o processo religioso conhecido como melichah, que consiste de três etapas: imersão em água, salga e dessalga das carcaças. Alguns estudos indicam que a salga pode ser benéfica para a qualidade microbiológica do produto, mas não se encontrou referência às bactérias halotolerantes como o Staphylococcus aureus e nem aos micro-organismos aeróbios mesófilos em frangos. Os objetivos deste trabalho foram avaliar a influência da etapa de salga na população de S. aureus e de microorganismos aeróbios mesófilos, identificar as espécies de Staphylococcus não produtoras de coagulase presentes e caracterizar fenotípica e genotipicamente os isolados de S. aureus e demais espécies. Para tanto foram coletadas 304 amostras de carcaças de aves, sendo metade obtida antes da etapa de salga e a outra metade após a dessalga. S. aureus esteve presente em 13/304 (4,3%) amostras, sendo que nove foram coletadas antes da salga. A população média de S. aureus nessas amostras foi de 2,5x10 UFC/g antes da salga e 8,9 UFC/g após a des salga, e de micro-organismos aeróbios mesófilos foi de 5,4x103 UFC/g antes da salga e 4,5x103 após a dessalga, variação esta que pode ser considerada normal e não decorrente da etapa de salga. Face à baixa frequência de S. aureus nas amostras, simulou-se o melichah em laboratório, sendo que o processo levou à redução significativa (p<0,05) da população de S. aureus. Todos os isolados identificados como S. aureus pelos diferentes métodos empregados foram capazes de produzir coagulase, portavam o gene nuc que é específico para essa espécie, mas não apresentavam o gene mecA que codifica para a resistência à meticilina. Em 88% (36/41) dos isolados identificados como S. aureus detectaram-se os genes codificadores para enterotoxina estafilocócica (SE) G e I, mas não os genes para as enterotoxinas clássicas. A maioria (37/41, 90,2%) desses isolados foi sensível aos antibióticos testados. Dentre as 890 colônias de Staphylococcus não produtoras de coagulase foram selecionadas 250 para serem submetidas à especiação, representando as diferentes amostras de aves. Foram identificadas as espécies S. hyicus (35%), S. cohnii subsp. urealyticus (29%), S. simulans (18%), S. epidermidis (6%), S. capitis (6%), S. hominis (2%), S. xylosus (2%), S. sciuri (1%), S. saprophyticus (1%) e S. warneri (0,4%). Destes isolados, foram selecionados 182 que foram avaliados quanto à sua capacidade de produzir enterotoxinas clássicas (kit VIDAS®), sendo que apenas três deles foram positivas, tendo sido detectada a presença somente de gene sec. Esses isolados eram da espécie S. epidermidis. Com relação à sensibilidade aos agentes antimicrobianos, verificou-se que 80% (148/185) foram resistentes a pelo menos um dos agentes testados, sendo a maior percentagem deles resistente à tetracicilina. Os resultados indicam que o abatedouro trabalha seguindo Boas Práticas de Fabricação (BPF) e que as aves produzidas apresentam baixo risco de disseminação de Staphylococcus produtores de toxina ou resistentes a agentes antimicrobianos. A etapa do melichah pode contribuir para a redução desse patógeno na superfície das carcaças. .In the Schechita slaughter, different from the conventional slaughter, there is a religious process called melichah that is be divided in three steps: immersion in water, salting and washing the carcasses. Some studies indicate that the salting step may benefit the microbial quality of the product, but no information concerning its influence on halotolerant bacteria such as Staphylococcus aureus or on mesophilic aerobes bacteria in poultry. The objectives of this study were to evaluate the influence of the salting step in the population of S. aureus and mesophilic microorganisms; to identify the species of coagulase negative Staphylococcus and to characterize, pheno and genotypically, the isolates. A total of 304 poultry carcasses were sampled, being half collected before salting and half after desalting steps. S. aureus was found in 13/304 (4.5%) samples being nine collected before salting. Average population of S. aureus in pre-salting carcasses was 2.5 x 10 CFU/g and 8.9 CFU/g after salt removal. Mean mesophlic aerobes population was5.4 x 103 CFU/g and 4.5 x 103 CFU/g for carcasses collected before salting and after washing steps, respectively. This variation can be considered normal and not derived from the salting step. As the frequency of S. aureus in the samples was low, the melichah was simulated in the lab showing that the process can reduce (p<0.05) the population of S. aureus. All isolates of S. aureus were able to produce coagulase, harbored the gene nuc (specific for the species) but not mecA that encondes for methicilin resistance. Amongst the S. aureus isolates 88% (36/41) harbored genes coding for staphylococcal enterotoxin (SE) G and I, but no genes for classical SE. The majority of these isolates (37/41, 90.2%) were sensitive to all antibiotics tested. 250 colonies, representing the different poultry samples were selected amongst the 890 coagulase negative Staphylococcus colonies for further identification. The species S. hyicus (35%), S. cohnii subsp. urealyticus (29%), S. simulans (18%), S. epidermidis (6%), S. capitis (6%) S. hominis (2%), S. xylosus (2%), S. sciuri (1%), S. saprophyticus (1%) and S. warneri (0,4%) were identified. Amongst the 250 isolates identified 182 were selected for classical SE production evaluation (kit Vidas®) being only three positive. The gene sec was detected in these isolates, and had been identified as S. epidermidis. Antibiotic resistance was observed in 80% (148/185) of the coagulase negative isolates, and tetraciclin resistance was the most frequent phenotype. The results indicate that this slaughterhouse applies good manufacturing practices (GMP) and that the poultry produced present low risk in disseminating enterotoxin producing or antibiotic resistant Staphylococcus. The melichah may contribute to the reduction of the pathogen in the surface of the carcasses.
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Paiva, Jeferson Leandro de [UNESP]. "Avaliação microbiológica da alface (Lactuca sativa) em sistema de cultivo hidropônico e no solo, correlacionando os microrganismos isolados com os encontrados em toxinfecções alimentares em municípios da região Noroeste de São Paulo - SP." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/94842.
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000642743.pdf: 1481069 bytes, checksum: 9eadf983610de6546b09d759783f8618 (MD5)A coleta da alface (Lactuca sativa) e da água de manejo foi realizada no local de cultivo, tanto pelo método de hidroponia (CH) como pelo tradicional no solo (CT) em estabelecimentos hortifrutigranjeiros e restaurante (R) localizados em cidades da região noroeste paulista. As vinte e cinco amostras analisadas foram coletadas em dias alternados, sendo cinco amostras de cada local. As análises foram realizadas com objetivo de verificar se a origem das toxinfecções alimentares envolvendo pratos que contenham alface é proveniente de microrganismos do local de produção das hortaliças. Os resultados obtidos possibilitaram analisar a ocorrência de contaminação cruzada com outras hortaliças enxaguadas no mesmo tonel e comparar o índice de contaminação dos dois tipos de sistema de cultivo. As análises microbiológicas seguiram as metodologias tradicionais descritas por Silva; Junqueira e Silveira (2001), de acordo com a American Public Health Association. Os resultados das análises mostraram grande variação na contagem dos microrganismos. Nas amostras de alface 92% (23) apresentaram crescimento de coliformes totais variando entre 0,4 a ≥240 NMP/g dos quais 40% (10) CT, 32% (8) CH, 20% (5) R; 32% (8) apresentaram coliformes termotolerantes variando entre 0,9 a 46 NMP/g, sendo 24% (6) CT e 8% (2) R; 36% (9) apresentaram Staphylococcus coagulase positiva, onde 12% (3) apresentaram crescimento acima dos parâmetros estabelecidos 5x103 UFC/g, sendo 4% (1) CT e 8% (2) CH. Todas as amostras positivas para coliformes termotolerantes estão dentro dos limites estabelecidos pela ANVISA (BRASL, 2001) de 102 UFC/g. Nenhuma amostra foi positiva para Salmonella spp, atendendo os parâmetros estabelecidos pela ANVISA (BRASIL, 2001) de ausência em 25g do produto. Os resultados obtidos nas análises da água foram de 95% (19) apresentando coliformes totais variando...
The collect of lettuce (Lactuca sativa) and the water used to grow it was made in the local of its cultivation through both hydroponics (CH) and the traditional in the soil (CT) methods in fruit/vegetable/poultry stores and restaurants (R) localized in the cities of the Paulista northwest region. The twenty-five samples analyzed were collected in alternate days, being five samples from each place. The analyses were carried out with the target to check if the origin of food toxinfection involving dishes that have lettuce is from microorganisms of the local where the vegetables are cultivated. The results obtained enabled to analyze the occurrence of contamination crossed with other vegetables rinsed in the same cask. Besides, to compare the rate of contamination of the two kinds of cultivation. The microbiological analyses followed the traditional methodologies written by Silva; Junqueira e Silveira, (2001), according to the American Public Health Association. The results of the analyses showed a great variation on the count of the microorganisms. In the lettuce samples 92% (23) presented growing of total coliforms varying between 0, 4 to ≥ 240 NMP/g from which 40% (10) CT, 32% (8) CH, 20% (5) R; 32% (8) presented thermotolerant coliforms varying between 0,9 to 46 NMPg, being 24% (6) CT and 8% (2) R. 36% (9) presented coagulase-positive Staphylococcus, where 12% (3) presented growing over the parameters established 5x103 UFC/g, being 4% (1) CT and 8% (2) CH. All the positive samples for thermotolerant coliforms are inside the limits established by ANVISA (BRASIL, 2001) of 102 UFC/g. No sample was positive for Salmonella spp, attending the parameters established by ANVISA (BRASIL, 2001) of absence in 15g of the product. The results obtained from the analyses of the water were from 95% (19) presented total coliforms varying between... (Complete abstract click electronic access below)
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Xi, Zhiqun. "An investigation on the flavor compounds and texture in Chinese chicken meat." Click to view the E-thesis via HKUTO, 2000. http://sunzi.lib.hku.hk/hkuto/record/B42575655.
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McFarland, Elizabeth Adeline. "Studies of Campylobacter isolates from poultry." Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335563.
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Donelan, Amy K. "Consumer poultry handling behaviors." Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/20477.
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Master of ScienceHuman Nutrition
Delores H. Chambers
Understanding how consumers handle poultry can highlight gaps in consumer knowledge and practice of food safety. Quantitative research provides only a partial image, whereas qualitative data is helpful in gaining a complete picture of a shopper's behaviors. The objective of this study was to determine what poultry product microbes could potentially be transferred during purchasing and home storage; using a shop-along observational technique to observe actual shopping, transporting, and storing behavior of consumers with raw poultry products. In 71% (n=97) of the situations observed there was no visible hand sanitizer or wipes in the meat section of the grocery store. Plastic bags could be found in the meat section 85% (n=97) of the time, which only 25% of shoppers (n=82) used the bag for their poultry products. During transportation, the consumer bagged the poultry separately from other products in 71% of the observations. A majority of shoppers (59%) stored poultry without using a plastic bag or other container. Overall, there needs to be an increase in food safety education on the handling of poultry during purchasing, transporting, and storage.
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Paiva, Jeferson Leandro de. "Avaliação microbiológica da alface (Lactuca sativa) em sistema de cultivo hidropônico e no solo, correlacionando os microrganismos isolados com os encontrados em toxinfecções alimentares em municípios da região Noroeste de São Paulo - SP /." São José do Rio Preto : [s.n.], 2011. http://hdl.handle.net/11449/94842.
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Orientador: Fernando Leite HoffmannBanca: Vanildo Luiz Del Bianchi
Banca: Maria Luiza Silva Fazio
Resumo: A coleta da alface (Lactuca sativa) e da água de manejo foi realizada no local de cultivo, tanto pelo método de hidroponia (CH) como pelo tradicional no solo (CT) em estabelecimentos hortifrutigranjeiros e restaurante (R) localizados em cidades da região noroeste paulista. As vinte e cinco amostras analisadas foram coletadas em dias alternados, sendo cinco amostras de cada local. As análises foram realizadas com objetivo de verificar se a origem das toxinfecções alimentares envolvendo pratos que contenham alface é proveniente de microrganismos do local de produção das hortaliças. Os resultados obtidos possibilitaram analisar a ocorrência de contaminação cruzada com outras hortaliças enxaguadas no mesmo tonel e comparar o índice de contaminação dos dois tipos de sistema de cultivo. As análises microbiológicas seguiram as metodologias tradicionais descritas por Silva; Junqueira e Silveira (2001), de acordo com a American Public Health Association. Os resultados das análises mostraram grande variação na contagem dos microrganismos. Nas amostras de alface 92% (23) apresentaram crescimento de coliformes totais variando entre 0,4 a ≥240 NMP/g dos quais 40% (10) CT, 32% (8) CH, 20% (5) R; 32% (8) apresentaram coliformes termotolerantes variando entre 0,9 a 46 NMP/g, sendo 24% (6) CT e 8% (2) R; 36% (9) apresentaram Staphylococcus coagulase positiva, onde 12% (3) apresentaram crescimento acima dos parâmetros estabelecidos 5x103 UFC/g, sendo 4% (1) CT e 8% (2) CH. Todas as amostras positivas para coliformes termotolerantes estão dentro dos limites estabelecidos pela ANVISA (BRASL, 2001) de 102 UFC/g. Nenhuma amostra foi positiva para Salmonella spp, atendendo os parâmetros estabelecidos pela ANVISA (BRASIL, 2001) de ausência em 25g do produto. Os resultados obtidos nas análises da água foram de 95% (19) apresentando coliformes totais variando... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The collect of lettuce (Lactuca sativa) and the water used to grow it was made in the local of its cultivation through both hydroponics (CH) and the traditional in the soil (CT) methods in fruit/vegetable/poultry stores and restaurants (R) localized in the cities of the Paulista northwest region. The twenty-five samples analyzed were collected in alternate days, being five samples from each place. The analyses were carried out with the target to check if the origin of food toxinfection involving dishes that have lettuce is from microorganisms of the local where the vegetables are cultivated. The results obtained enabled to analyze the occurrence of contamination crossed with other vegetables rinsed in the same cask. Besides, to compare the rate of contamination of the two kinds of cultivation. The microbiological analyses followed the traditional methodologies written by Silva; Junqueira e Silveira, (2001), according to the American Public Health Association. The results of the analyses showed a great variation on the count of the microorganisms. In the lettuce samples 92% (23) presented growing of total coliforms varying between 0, 4 to ≥ 240 NMP/g from which 40% (10) CT, 32% (8) CH, 20% (5) R; 32% (8) presented thermotolerant coliforms varying between 0,9 to 46 NMPg, being 24% (6) CT and 8% (2) R. 36% (9) presented coagulase-positive Staphylococcus, where 12% (3) presented growing over the parameters established 5x103 UFC/g, being 4% (1) CT and 8% (2) CH. All the positive samples for thermotolerant coliforms are inside the limits established by ANVISA (BRASIL, 2001) of 102 UFC/g. No sample was positive for Salmonella spp, attending the parameters established by ANVISA (BRASIL, 2001) of absence in 15g of the product. The results obtained from the analyses of the water were from 95% (19) presented total coliforms varying between... (Complete abstract click electronic access below)
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Atterbury, Robert J. "Bacteriophage control of Campylobacters in retail poultry." Thesis, University of Nottingham, 2004. http://eprints.nottingham.ac.uk/14066/.
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Food-borne disease continues to be a major cause of human morbidity and mortality. During the past few decades, Campylobacter jejuni has ascended to become the greatest cause of bacterial enteric disease worldwide. Anecdotal evidence suggests the majority of human campylobacteriosis in industrialised countries is caused by the consumption of undercooked chicken. Campylobacter continues to frustrate current control strategies throughout the food chain and in 2001 was responsible for over 56, 000 cases of food poisoning in the U.K. alone. The work presented in this thesis examined the potential of host-specific bacteriophage as a novel measure to control the population of Campylobacter in poultry production. Several surveys in this thesis revealed that campylobacters and their bacteriophage permeate the entire poultry meat supply chain, from chickens in the broiler house to packaged retail products. Characterisation of the bacteriophage recovered from such sources showed that retail poultry isolates exhibited greater similarities in host range than those originating from broiler houses, implying poultry processing selected for a subpopulation of phage. Additionally, broiler chickens harbouring bacteriophage in their gastrointestinal tract generally contained fewer campylobacters. All of the phage isolates studied belonged to the Myoviridae virus family as they possessed dsDNA genomes encapsulated in an icosahedral head with a rigid, contractile tail. Fragments of the phage genomes exhibited significant sequence homology with a number of genes involved in DNA replication from phage T4. Studies of the attachment and replication of the phage isolates in vitro suggested that adsorption to the host cell was efficient but the burst size was low (˂10 virions per cell). Campylobacter jejuni was found to produce membrane vesicles but these did not significantly affect bacteriophage replication in vitro. A series of trials using 'phage therapy' in broiler chickens revealed that Campylobacter colonisation can be reduced by ≥log[subscript]10 8.0 cfu g[superscript]-1 caecal contents by dosing with specific bacteriophage. However, both the timing and extent of the reduction in Campylobacter colonisation showed considerable variation. Additionally, the ability of bacteriophage to infect their host in vitro was not a reliable indicator of their efficacy in vivo. The direct application of bacteriophage to the surface of chicken skin artificially contaminated with Campylobacter led to a significant reduction in the number of recoverable host cells. Host resistance to bacteriophage infection was not detected in either the in vivo trials or when recovering Campylobacter cells from chicken skin treated with phage. The work presented in this thesis demonstrates that bacteriophage have considerable potential in the control of Campylobacter in poultry production. They already appear to constitute a limiting factor in Campylobacter colonisation of the chicken gastrointestinal tract and can be detected with their host on retail products. However, further research is required to fully realise their potential and optimising the timing, level and type of bacteriophage used in dosing will be important for their efficacy in vivo.
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Vadari, Yoganand. "Estimation of Microbial Diversity in Poultry Litter Using Terminal Restriction Fragment Length Polymorphism and Isolation of Phosphate Accumulating Bacteria from Poultry Litter." TopSCHOLAR®, 2004. http://digitalcommons.wku.edu/theses/239.
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The contamination of fresh water by phosphates in poultry litter results in substantial eutrophication of fresh water causing fish kills and other types of environmental damage. The poultry indus try in Kentucky is expanding rapidly. The number of broilers is increasing as more poultry farms are established in the state producing waste that needs disposal. Investigations were made to study the possibility of using microorganisms normally found in poultry litter to sequester phosphate, thereby delaying phosphate runoff after litter is applied to croplands. Little is known, however, about the microflora of poultry litter. Terminal restriction fragment length polymorphism of 16S rDNA from bacteria was used to investigate the bacterial diversity of poultry litter. Poultry litter was collected from a local producer. DNA was isolated using commercial kits and amplified using the polymerase chain reaction with primers specific for bacterial 16S rDNA. The amplified fragments were digested using HhaI restriction endonuclease and the DNA fragment lengths were determined. To determine the sensitivity of this method, known quantities of Escherichia coli cells were spiked into litter prior to DNA extraction. Successful amplification of the bacterial rDNA was highly variable but could be improved by passing the purified DNA through two purification columns in lieu of only one column. The detection threshold for E. coli was 10 cells, however, the results also varied widely. Bacteria capable of hyper-accumulating intracellular phosphate were isolated from poultry litter as possible tools for phosphate remediation in poultry litter. Five strains of phosphate accumulating bacteria were successfully isolated from poultry litter. Poultry litter was suspended in sterile nanopure water and 100μl was plated on BHI plates containing an addtional 750mM K2HPO4. Isolated colonies were screened for intracellular metachromatic granules using the Nile blue stain, a presumptive test for polyphosphate. Positive colonies were cultured in BHI and BHI with supplementation of K2HPO4 and free intracellular phosphate concentrations were determined in cell extracts. Total phosphates were measured in cell extracts subjected to hydrolysis by addition of 12N HCl and heating at 100°C for 60 min. Polyphosphate was determined by subtraction of free phosphates from total phosphates. Results showed five isolates of gram-positive bacteria were obtained from poultry litter. All isolates were cocci arranged in chains or clusters and were catalase positive. All isolates showed considerable levels of intracellular phosphate accumulation, which were comparable to Microlunatus phosphovorus, a bacterium known to hyper-accumulate phosphate. Biolo g analysis indicated four of the five strains isolated were Staphylococcus sp. and one strain was unidentified.
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Terry, Taylor Lauren. "Food handling behaviors of consumers when grilling poultry." Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/38267.
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Master of ScienceDepartment of Food, Nutrition, Dietetics and Health
Mark D. Haub
Research has shown that many consumers do not use the proper food safety practices when cooking in the home. Although many studies have been conducted to observe the food safety behaviors and practices in a domestic home kitchen, the food safety behaviors of consumers when using an outside grill has not been vastly explored. The objective of this study was to gain insight on consumers' food safety practices and behaviors when preparing meat and poultry on an outdoor grill. A nationwide survey of grilling consumers (n=1024) was conducted to evaluate the food handling behaviors of consumers who use an outdoor grill to prepare meat and poultry. The survey consisted of 50 questions based on the four core practices of food safety: clean, separate, cook, and chill. The results showed that there was low adherence to consumers not rinsing meat or poultry before preparation, separating utensils for raw and cooked meat, and using a thermometer to ensure doneness. Respondents who grilled poultry followed safer food handling practices than respondents who grilled meat. An observational study (n=30) was conducted to observe consumers prepare poultry products on an outdoor grill. Participants were assessed on handwashing skills, cross contamination behavior, and how they determined the doneness of the poultry. This study illustrated that consumers were not washing their hands thoroughly, especially after handling packaging. Many consumers were observed contaminating surfaces or items in their kitchen after touching the raw poultry. Consumers also failed to use clean utensils for the cooked poultry after using the utensil on raw poultry. Consumers used several methods to determine the doneness of the poultry. Visual cues such as looking at the appearance or color of the poultry was primarily used by consumers to check if the poultry was fully cooked, followed by piercing or cutting the poultry open and using a thermometer. Thermometer use in this study was found to be higher than the usage in prior studies. A separate study assessed poultry grilling recipes (n= 242) for a specified temperature of doneness and additional food safety information. Recipes from cookbooks, magazines, and online sources were evaluated. Over half of the recipes did not specify a temperature of doneness, but used time, visual or textural indications to determine doneness. The findings of this research show that consumers could benefit from education to improve their food handling skills when preparing meat or poultry on an outdoor grill. Educational efforts should focus on proper handwashing procedures, how to reduce cross contamination and the importance of using a thermometer to ensure doneness.
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Robinson, Tobin. "The microbiology of food microenvironments." Thesis, Cardiff University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387586.
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Olaonipekun, Basirat Arinola. "Application of predictive food microbiology to reduce food waste." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/65935.
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Universal food insecurity continue to be a challenge that needs attention from all stakeholders. The problem of food waste however is highly important as it slows down the effort to improve food security, most especially in the world’s poorest countries. Conservative shelf life estimation of RTE foods by food producers is one of the major contributor to food waste. After a survey was carried out on the different RTE food products (n=195) available on the shelf of 3 supermarkets in Hatfield, with their set shelf life and storage instructions. Microbiological quality (Total viable count, LAB, Enterobacteriaceae, yeasts and moulds, and Pseudomonas spp.) and safety (E. coli, Staphylococcus aureus, Listeria spp. and Salmonella spp.) was conducted on selected RTE products (used as a reference point) during storage at ± 5o C. This wass to evaluate the validity of the set shelf life of beef lasagne (3 days), egg noodles (3 days), pre-cut mango (4 days) and pre-cut papaya (4 days) by food producers. Challenge test study was also conducted on representative RTE food products (beef lasagne, egg noodles, and pre-cut mango) with relevant food borne pathogens (L. monocytogenes, Salmonella Typhimurium, and E. coli) during storage for 12 days at ± 5oC. Growth potential (?) of these pathogens in the RTE foods were calculated using the concept of EU-CRL technical guidance on shelf life for L. monocytogenes on RTE foods as ? values can be very useful in potential food safety risk evaluation. Performance of 4 different types of software (ComBase, PMP, MicroHibro & FSSP) was evaluated for use in shelf life estimation of these selected RTE foods. These software were selected based on different criteria (User-friendly, accessibility and availability and types of pathogens for its application). The predicted growth from these software were compared to observed growth (generated from experimental data got from challenge test) of L. monocytogenes in beef lasagne and egg noodles. Indices of performance; Coefficient of determination (R2), root mean square error (RMSE), bias factor (Bf) and accuracy factor (Af) were used to evaluate the performance of these software. All the RTE food products reviewed had no specific refrigeration storage temperature instruction on the product package. Storage test study indicated that some of these RTE foods (beef lasagne, pre-cut mango and papaya) could have longer shelf life (5, 13 and 5 days respectively), while egg noodles could be a potential public health risk due to the presence of food borne pathogens right from day of purchase. However, the challenge test results also confirmed the conservative shelf life estimation by food producers in that the shelf life of all the products evaluated can be extended (Beef lasagne by 6 days, Egg noodles by 6 days and pre-cut mango by 9 days) with no food safety risk associated with the extension. On the other hand. RTE egg noodles and beef lasagne may support the growth of L. monocytogenes (? > 0.5 log10 cfu/g) if present in the food while egg noodles may not support the growth of S. Typhimurium (? ? 0.5 log10 cfu/g). Beef lasagne and pre-cut mango may also not support the growth of E. coli (? ? 0.5 log10 cfu/g). Growth of L. monocytogenes predicted by ComBase, PMP, MicroHibro & FSSP in beef lasagne and egg noodles was in agreement with the observed growth from the challenge test study, with a fail-safe prediction. However, ComBase predictor had the closest prediction to the observed growth. Hence, it had overall best performance for prediction compared to the other software. Notwithstanding, all the software evaluated in this study can be applied in shelf life prediction of RTE food products. Predictive microbiology is a field of food microbiology that can be looked into and implemented by the authorities. Its use by the South African food industry to scientifically estimate the shelf life of RTE food products is thereby encouraged. This will assist in decision making with regards to food quality and safety, thereby reducing the problem of food waste as result of product shelf life and at the same time protect public health.Dissertation (MSc)--University of Pretoria, 2017.
Food Science
MSc
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Grant, Irene Ruth. "The microbiology of irradiated pork." Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335332.
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Greene, Donna Mechelle. "Use of Poultry Collagen Coating and Antioxidants as Flavor Protection for Cat Foods Made with Rendered Poultry Fat." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/9848.
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Poultry skins and rendered poultry fat are by-products produced in excess at rendering plants. The use of low value by-products such as poultry collagen, from poultry skins, and fat to improve flavor and quality in dry pet food could be economically attractive. This study examined a poultry collagen coating as a protective barrier against oxidation in dry cat food made with rendered poultry fat. Collagen was extracted from chicken skins, dissolved in an acidic solution, applied to dry cat food and dried to form a surface film. Six treatments were examined: kibble, kibble with fat, kibble with collagen, kibble with fat and collagen, kibble with fat, BHA/BHT and collagen and kibble with fat, tocopherol and collagen. There were two storage conditions: ‘jungle condition’ (42°C and 83% relative humidity) and ‘ambient condition’ (21°C and 51% relative humidity). In ‘jungle conditions’, thiobarbituric acid reactive substances (TBARS) was measured
over an eight-day period at day 0, 2, 4, 6, and 8. In ‘ambient conditions’, TBARS was measured over a thirty-day period at day 0, 7, 14, 21, and 30. Water activity and moisture contents were measured. There were significantly higher TBARS (P<0.05) for the control kibble at both storage conditions. There was significantly higher fat percentage (P<0.05) in all treatments with the additional fat coatings. Fatty acid compositions showed slight changes during storage. There were some changes in the aroma profile of the kibble with fat treatment having musty, moldy and plastic aromas at both storage conditions. The volatile aromas might be an indication of oxidation in the poultry fat.Master of Science
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Zhou, Yang. "Antibiotic Resistance in Poultry Gastrointestinal Microbiota and Targeted Mitigation." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1471819231.
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Goeksoy, E. O. "Decontamination of poultry meat by intense heat treatment." Thesis, University of Bristol, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297810.
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Pope, Christopher E., and n/a. "Campylobacter jejuni : virulence, dosage, survival, and colonisation characteristics." University of Otago. Department of Microbiology and Immunology, 2005. http://adt.otago.ac.nz./public/adt-NZDU20070501.141243.
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In a previous study, twenty-five flaA types were detected among 200 Campylobacter jejuni isolates obtained from clinical and poultry meat sources.
The most common flaA type detected among poultry isolates was flaA-3 at a frequency of 23%. In contrast, flaA-3 constituted 5% of the clinical isolates. FlaA-15 was detected most frequently among clinical isolates (31%) but rarely among poultry isolates (5%). Purchasers of poultry meat were therefore commonly exposed to flaA-3 yet most of the human infections were due to flaA type 15. The prevalence of different flaA types in poultry and humans might have been due to: FlaA-15 was more virulent for humans than flaA-3 (infection more likely to result). There were more C. jejuni flaA-15 cells on poultry meat (dose effect). Better survival of flaA-15 cells when freeze/thawed or when stored at +4�C (survival in kitchen). Ecological performance of flaA-3 strains in chicken gut better than that of flaA-15 (more flaA -3 cells in gut therefore greater chance of carcass contamination)?
Eleven strains representing flaA types 3, 13, and 15 were tested for their ability to invade cultured human epithelial cells (HEp-2). Invasiveness was considered to reflect virulence. FlaA-15 isolates were more invasive in comparison to flaA-3 and flaA-13 isolates (p<0.0001).
Washings from chicken portions were cultured to enumerate Campylobacter cells present on the meat. C. jejuni isolates were flaA typed and the numbers were related to FlaA type. A correlation was not detected.
The eleven representative strains were used to inoculate 1 cm� sections of chicken skin which were stored at -20�C or +4�C over a five day period. The samples stored at -20�C were thawed and held either overnight at 25�C, overnight at +4�C or for thirty minutes at 25�C. The numbers of viable Campylobacter cells on the sections were determined. Survival ability differed from strain to strain but was not associated with flaA type.
The most invasive C. jejuni strain (T1016; flaA-15) and the least invasive strain (Pstau; flaA-3) were assessed for their ability to colonise the intestinal tract of one-day-old chicks. The dynamics of colonisation, after inoculation of the birds with pure cultures or with mixtures, was monitored by real-time quantitative PCR. Strain-specific primers based on the variable region of the nucleotide base sequence of flaA genes were derived for this work. This enabled the individual strains to be enumerated in gut contents from colonized chickens. Both strains could colonise the chick intestinal tract but C. jejuni strain T1016 (flaA-15) could competitively exclude PStau (flaA-3).
It was concluded that the higher prevalence of flaA-15 strains among the clinical isolates was due to its higher virulence for humans. In other words, despite a low prevalence of flaA-15 on poultry meat, infection was more likely to result when C. jejuni flaA-15 cells were consumed.
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Eames, Malcolm. "United Kingdom Government food research and development policy : food safety, food science and the consumer." Thesis, University of Sussex, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238807.
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Pozo, Veronica F. "Effects of meat and poultry recalls on firms' stock prices." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/18160.
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Doctor of PhilosophyDepartment of Agricultural Economics
Ted Schroeder
Food recalls have been an issue of great concern in the food industry. Stakeholder responses to food safety scares can cause significant economic losses for food firms. Assessing the overall impact that may result from a food recall requires a thorough understanding of the costs incurred by firms. However, quantifying these costs is daunting if not impossible. A direct measurement of a firm’s total costs and losses of revenue associated with a food recall requires firm-level data that is not available. The method utilized in this study overcomes this severe limitation. Using an event study, the impact of meat and poultry recalls is quantified by analyzing price reactions in financial markets, where it is expected that stock prices would reflect the overall economic impact of a recall. A unique contribution of this study is evaluating whether recall and firm specific characteristics are economic drivers of the magnitude of impact of meat and poultry recalls on stock prices. Results indicate that on average shareholders’ wealth is reduced by 1.15% within 5 days after a firm is implicated in a recall involving serious food safety hazards. However, when recalls involve less severe hazards, stock markets do not react negatively. Also, reductions in company valuations return to pre-recall levels after day 20. Firm size, firm’s experience, media information and recall size are drivers of the economic impact of meat and poultry recalls. That is, firms recalling a larger amount of product perceive greater reductions in company valuations. Additionally, recalls issued by larger firms are less likely to present negative effects on stock prices, compared to smaller firms. Moreover, firms that have recently issued a recall are less harmed by a new recall compared to those firms issuing a recall for first time. Thus, suggesting that investors take into consideration the past performance of a company when dealing with food recalls. Furthermore, media information has a negative impact on shareholder’s wealth. Findings from this study provide essential information to the meat industry. In particular, understanding the likely impact of such “black swan” events is critical for firm’s investing in food safety technologies and protocols.
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De, Beer H., and C. J. Hugo. "Potential sources of chryseobacterium contamination during poultry processing : a pilot study." Journal for New Generation Sciences, Vol 8, Issue 3: Central University of Technology, Free State, Bloemfontein, 2010. http://hdl.handle.net/11462/566.
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Published ArticleThe genus Chryseobacterium is often found in food and is regarded as a food spoilage organism. In this study, the source of the chryseobacteria was uncertain. As an exploratory investigation, the potential source of chryseobacterial contamination was determined. Total bacteria counts and yellow-pigmented colony counts were performed. Chryseobacterium species were present on poultry carcasses at all stages of processing. Total Chryseobacterium counts increased from 5.6 to 11.8 % after the brine injection stage. A significant increase in total Chryseobacterium counts (20.0 and 25.2 %) in the processing waters occurred where cutting up of the carcasses was involved. It is speculated that live chickens are the source of contamination.
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Mendoza, L. S. "The microbiology of cooked rice and fish fermentation." Thesis, University of Reading, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356490.
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Fan, Min. "Fate and transport of herbicides in a sandy soil in the presence of antibiotics in poultry manures." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86927.
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Antibiotics are widely used in the livestock industry for preventing disease and improving feed efficiency. Many antibiotics are not completely absorbed by animals and they are excreted in urine and feces. When manure containing such antibiotics is used as a fertilizer, it can affect the degradation of pesticides since antibiotics inhibit the action of bacteria in soils or kill the bacteria. A ninety-day field lysimeter study was conducted to assess the effects of antibiotics on the degradation of three herbicides, atrazine, metribuzin and metolachlor, in a sandy soil. Poultry manures, respectively containing monensin, narasin and salinomycin, were used to investigate the effects of antibiotics on the degradation of herbicides, and were compared with a control treatment of manure without antibiotics. Herbicides were applied once to the soil surface of lysimeters at the locally recommended rates, followed by the application of poultry manures. The lysimeters were protected from natural rainfall, and the simulated rainfall was applied seven times. Both soil and leachate samples were collected and analyzed at predetermined time intervals. In the experiment, all the three herbicides were found to leach down through the soil profiles, and their concentrations decreased with soil depth and time. The statistical analysis of the results shows that all the three antibiotic treatments yielded a significantly slower dissipation of herbicide levels compared with the non-antibiotic treatment. The mass balance study reveals that the half lives of the three herbicides were significantly longer in the presence of antibiotics as compared to the control treatment without antibiotics. These results indicate that antibiotics in poultry manures can significantly slow down the degradation of the three herbicides in soil and therefore, increase the threat of herbicide pollution in the environment.Les antibiotiques sont couramment utilisés dans l'industrie du bétail pour prévenir les maladies et améliorer l'efficacité flux. Beaucoup d'antibiotiques ne sont pas complètement absorbés par les animaux et ils sont excrétés dans les urines et fèces. Lorsque le fumier contenant des antibiotiques est utilisé comme un engrais, il peut affecter la dégradation des pesticides puisque les antibiotiques contenus inhiber l'action de bactéries dans le sol ou tuer ces bactéries. Une étude de lysimètre de champ de quatre-vingt-dix-jour a été effectuée pour évaluer les effets des antibiotiques sur la dégradation de trois herbicides, atrazine, métribuzine et métolachlore, dans un sol sableux. Trois traitements des fumiers de volaille contenant monensine, narasine et salinomycine ont été utilisés pour étudier les effets des antibiotiques sur la dégradation des herbicides, et ont été comparés avec un traitement de contrôle de fumier sans antibiotiques. Herbicides étaient appliqués une fois à la surface de sol de lysimètres aux taux recommandés localement, suivie par l'application de fumiers de volaille. Les lysimètres ont été protégés des précipitations naturelles, et les précipitations simulées ont été appliqués sept fois. Des échantillons de sol et des échantillons d'eau ont été recueillis et analysées à intervalles de temps prédéterminés. Dans l'expérience, tous les trois herbicides ont été trouvés à s'infiltrer à travers les profils de sol et leurs concentrations ont diminués avec la profondeur du sol et de temps. L'analyse statistique des résultants ont montré que tous les trois traitements antibiotiques ont donnés une dispersion des niveaux d'herbicide sensiblement plus lent par rapport au traitement nonantibiotic. L'étude du bilan massique a révélé que les demi-vies des herbicides ont été significativement plus long avec l'utilisation d'antibiotiques comme par rapport au ce traitement de contrôle s
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Robles, de la Terre Raul Rene. "Modelling continuous solid/liquid countercurrent food extractions." Thesis, University of Reading, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363805.
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Xi, Zhiqun, and 習志群. "An investigation on the flavor compounds and texture in Chinese chicken meat." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B42575655.
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Shefet, Sarid M. "Development of nisin-based treatments to control pathogenic and spoilage microorganisms associated with poultry products." NCSU, 1997. http://www.lib.ncsu.edu/theses/available/etd-19970911-110240.
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SHEFET, SARID M.
More than 10% of the U.S. population experience at least one incident of foodborne disease annually (Todd, 1989). From 1983 to 1987, infections contribute to at least 1,000 deaths per year in the United States.
Poultry products are considered to be the single most important food source of contamination rates for live chickens can vary from about 13% to 80% of the flock and are invariably higher after processing (Mead, 1976; Roberts, 1988; Budnik, 1990). In 1992, the U.S. was ranked first in the world in poultry consumption with 94.8 pounds per capita, followed by Israel with 83.7 pounds, and Hong Kong with 79.3 pounds (Brown, 1993). In 1993 over 27.6 billion pounds of ready-to-cook poultry products were produced in the U.S. Per capita consumption of poultry products has increased substantially over the last two decades relative to other meat products; therefore, exposure of the consumer to poultry product-associated microorganisms including pathogens has correspondingly increased and no doubt contributes to these foodborne disease statistics.
Besides bacterial pathogens, poultry products are also contaminated with a variety of spoilage microorganisms which can contribute to the development of strong off odors and/or slime formation and shortened product shelf life. These organisms, however, are not generally associated with human illness. A reduction in the population of these microorganisms or suppression of their growth often results in increased product shelf life and greater consumer acceptability. Some reports have estimated that the presence of pathogenic and spoilage microorganisms on poultry may cost the American public over two billion dollars annually in foodborne disease-related expenditures and spoiled products (Roberts, 1988; Todd, 1989).
The bacteriocin nisin was approved by the United States Food and Drug Administration in 1988 as a GRAS (general recognized as safe) substance for use in pasteurized cheese spreads to control outgrowth and toxin production by Clostridium botulinum. Blackburn when combined with chelating agents such as disodium ethylenediamine tetraacetate (EDTA) and citrate. Perturbation of the outer membrane of gram-negative bacteria via chelation of divalent cations located in the lipopolysaccharide layer is believed to sensitize the cells by providing access to the cytoplasmic membrane where nisin-mediated inactivation occurs.
The initial focus of this study was to optimize the inhibitory activity of nisin against a NAR skin population, as observed with broiler drumstick skin, were detected following treatment with the four nisin-containing treatments.
Experiments were also conducted to determine the efficacy of the nisin-based treatments against NAR-infected drumstick skin under varying exposure times and concentrations of nisin. Exposure time significantly influenced the lethality of the treatments and depending on the treatment, nisin concentrations could be reduced from 100 µg/ml to 50 or 25 µg/ml without loss of significant biocidal activity. In other studies, the refrigerated shelf life of broiler drumsticks was extended by 1.5 to 3 days following immersion for 30 minutes in one of the optimized nisin-containing treatments in comparison to drumsticks immersed in distilled, deionized water.
These findings indicate that treatments containing nisin and varying concentrations of chelating agents and/or surfactant at an acidic pH are capable of significantly inhibiting the population of -free poultry products, the identification and implementation of effective preservation methods could result in several long term benefits including greater public confidence in poultry products, an increased market potential, and increased profits for the poultry industry.
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Gagnon, Carole Chantalle. "Detection of avian leukosis virus in the laboratory and in naturally infected poultry flocks using the polymerase chain reaction." Thesis, University of Ottawa (Canada), 1997. http://hdl.handle.net/10393/10309.
Full textAbstract:
Commercial poultry operations continuously test for the presence of avian leukosis virus (ALV) in their flocks. Tests currently in use for detecting ALV are ELISA (enzyme-linked immunosorbent assay)-based and detect either specific viral proteins or antibodies that are raised against ALV upon infection. Regions of the ALV genome have been identified which differentiate endogenous from exogenous ALV and these areas have been targeted with PCR primers. Using semi-nested PCR amplification of the LTR (long terminal repeats), we were able to detect all four subgroups of exogenous viruses affecting chickens (A, B, C and D). Two other sets of semi-nested primers targeted within the variable regions of the env (envelope) gene are able to determine the subgroup, A or B (the predominant subgroups infecting North American flocks), of the infecting virus. These sets of primers were first tested on chick embryo fibroblasts (CEF) not carrying any ev genes. The cells were infected with viral isolates of subgroups A (RAV-1), B (RAV-2), C (RAV-49) and D (RAV-50). The LTR primers detected all four subgroups, while the env primers detected only the virus of the subgroup for which they were designed. (Abstract shortened by UMI.)
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Stuart-Moonlight, Belinda Isobel. "Microbial survival on food contact surfaces in the context of food hygiene regulation." Thesis, King's College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249535.
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Maughan, Curtis A. J. "Making preparation of poultry and eggs safer for consumers: a focus on recipes and temperature." Diss., Kansas State University, 2015. http://hdl.handle.net/2097/20538.
Full textAbstract:
Doctor of PhilosophyHuman Nutrition
Edgar Chambers IV
Consumer food safety often is lacking, with many studies showing that we need to understand consumer behavior better and find new ways to provide information. The objective of this research was to better understand consumer food safety behaviors, find possible avenues for communicating food safety instructions to consumers, and determine how those avenues could work for demonstrating food safety today. Results from this research showed that two of the main potential avenues for communicating food safety instructions, namely recipes and cooking shows, were wholly lacking in good information and behaviors. A survey of egg dish recipes found that almost none contained temperature information, despite recommendations of food safety agencies. Observing celebrity chefs prepare food showed that every chef repeatedly had poor food safety practices which would lead to foodborne illness if followed by consumers at home. Two consumer studies were done with observers watching consumers prepare poultry and egg items. In the first study, consumers were asked to prepare poultry and egg items using both stovetop and oven methods. This study demonstrated that consumers do not follow many food safety behaviors, such as hand washing and using thermometers, and that those who used a thermometer were not better at reaching a safe temperature than those who didn’t use one. The second study had consumers prepare poultry items following a recipe, with half receiving food safety instructions on hand washing and thermometer use with their recipes. This study demonstrated that the addition of food safety instructions dramatically improved food safety behaviors in consumers. A separate study looked at the effect of changing lighting due to recent changes in efficiency regulations. This study found that some forms of modern lighting, such as LEDs, are more likely to make consumers think that poultry products are finished cooking before they are done, showing an even greater need for thermometer use. These studies present a message for the industry: food safety information and behaviors are lacking in consumers, but simple efforts such as adding food safety instructions to recipes can make consumers more aware of appropriate behaviors and improve their food safety.
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de, Senna Antoinette BoYee. "Screening of biocontrol organisms for the management of phytopathogenic fungi and foodborne pathogens on produce." DigitalCommons@CalPoly, 2015. https://digitalcommons.calpoly.edu/theses/1402.
Full textAbstract:
The multibillion dollar agricultural industry is an important part of the United States economy, and the management of factors that affect crop and human health is imperative to maintaining this economic sector. The fungi Botrytis cinerea, Fusarium pallidoroseum, and Fusarium moniliforme are the causative agents of several plant diseases and can cause significant crop loss both before and after harvest in commodities such as strawberries, lettuce, citrus, and grains. Fungicides are employed to control these phytopathogens, but the use of these chemicals has led to an increase in fungicide resistance and may negatively affect the environment and human health. In addition to plant pathogens, foodborne pathogens also have a substantial impact on the agricultural industry. Foodborne disease outbreaks involving Listeria monocytogenes, Salmonella, and Escherichia coli O157:H7 not only cause considerable economic losses, but can also result in devastating health problems for consumers. The increase in fungicide resistance and number of produce-related foodborne disease outbreaks warrants investigation into additional methods of microbial control for use in the agricultural industry. Many bacterial species, including Lactic Acid Bacteria (LAB) and Bacillus species, produce antifungal and antimicrobial compounds, thus the use of biological control agents pre- and postharvest could augment current methods of pathogen management. The purpose of this study was to screen 22 bacterial isolates for inhibitory activity against the fungal phytopathogens Botrytis cinerea, Fusarium pallidoroseum, and Fusarium moniliforme and the foodborne pathogens Listeria monocytogenes, Salmonella, and Escherichia coli O157:H7 in vitro, then evaluate antimicrobial efficacy of select isolates against the foodborne pathogens on fresh produce.
To evaluate antifungal activity, the bacterial isolates were individually spot-inoculated onto Tryptic Soy Agar, Potato Dextrose Agar, or MRS agar, depending on isolate growth requirements and then a plug of fungal-colonized agar was placed onto the center of the isolate-inoculated plate. Plates were incubated at 24°C for 10 days; fungal growth was evaluated daily, beginning on Day 3. Nine of the 22 isolates screened inhibited all three fungi; inhibition by these isolates ranged from 51-62% for B. cinerea, 60-68% for F. pallidoroseum, and 40-61% for F. moniliforme. Isolates were also screened for biosurfactant activity using the drop-collapse test. Biosurfactant production was detected in seven of the nine isolates. Bacillus megaterium, Bacillus coagulans, Bacillus thuringiensis BT2 and three Bacillus amyloliquefaciens isolates demonstrated strong biosurfactant activity and suppression of all three fungi, and therefore are recommended for further study.
Antimicrobial activity of the isolates was assessed using two methods: LAB isolates were screened using a seeded-overlay method and all other isolates were evaluated by spot inoculating the isolate on pathogen-seeded TSA. Three LAB isolates and six Bacillus isolates suppressed L. monocytogenes, Salmonella, and E. coli O157:H7 in vitro. Based on the results of the screening, three LAB isolates—Lactobacillus plantarum, Pediococcus acidilactici, and Pediococcus pentosaceus—were selected for further evaluation and use in challenge studies on fresh produce.
The role of organic acids in pathogen inhibition was evaluated by incubating L. monocytogenes, Salmonella, and E. coli O157:H7 cultures in the cell-free supernatant (CFS; pH 3.81-4.27) or the neutralized cell-free supernatant (pH adjusted to 6.5 -7.0) of each isolate. When neutralized, the antimicrobial activity of the CFS of the three LAB isolates was greatly diminished, illustrating the role of lactic acid in the inhibition of pathogen growth.
To assess antimicrobial efficacy on Iceberg lettuce, a cocktail of the three LAB isolates (7-8 log CFU/g) was sprayed onto lettuce spot-inoculated with L. monocytogenes (2-3 log CFU/g); lettuce was incubated at 10°C for 14 d. L. monocytogenes levels were 1.84 log lower on LAB-treated lettuce than on untreated lettuce at the end of incubation. Because the LAB cocktail suppressed the growth of L. monocytogenes on lettuce, testing on fresh produce continued using DF1, which was a powdered product comprised of the three LAB isolates and media components. Because DF1 caused substantial browning of Iceberg lettuce after 2 d, Gala apples were chosen to evaluate the antimicrobial activity of DF1 against L. monocytogenes, Salmonella, and E. coli O157:H7.
The effect of DF1 on L. monocytogenes, Salmonella, and E. coli O157:H7 on Gala apples was determined by spraying a Gala apple spot-inoculated with pathogen (6-7 log CFU/plug) with approximately 3 mL of a 20% DF1 solution, then incubating at 20°C for 5 d. After 5 d incubation, L. monocytogenes, Salmonella, and E. coli O157:H7 levels on DF1-treated apples were approximately 4, 2, and 2 log higher than the control, respectively. Based on the results of these experiments, DF1 is not the optimal formulation for the biocontrol of foodborne pathogens on fresh produce.
This study identified several bacterial isolates with potential for use in the biocontrol of plant and foodborne pathogens. Further investigation is required to assess possible use in the agricultural industry, including characterization of bioactive compounds, optimization of biocontrol product formulation, and evaluation of the commercial viability of the biocontrol product
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Hong, Wan Soo. "The development of a methodology for assessing food quality in hospital food service systems." Thesis, Sheffield Hallam University, 1993. http://shura.shu.ac.uk/19824/.
Full textAbstract:
There are few empirical studies of food quality within hospital food service systems. Although it is widely accepted that food quality is a multi-faceted phenomenon, much attention has been paid to single component explanations in the past. The aim of this study throughout has been two fold - to develop a model suitable for evaluating the quality of food in conventional hospital food service systems; and to evaluate food quality in selected hospitals in the Trent Regional Health Authority and West Midland Regional Health Authority using the model. A key outcome in this study has been the development of a multifaceted measurement of food quality to help catering managers deploy resources effectively, in conventional hospital food service systems. This approach was achieved using a variety of qualitative and quantitative information to score six food quality components and 15 influencing variables. Food quality was defined as a multi-dimensional measure to include measures of satisfaction of patients and catering staff, productivity, safety, and nutritional adequacy. Measures of influencing variables were chosen or adapted from those available in food service operations insofar as was possible. Where none was available, methods were developed. The variables were grouped into two major categories: human resources and system resources. A survey of 12 hospital conventional food service systems in the UK was undertaken and detailed information was collected from each, including surveys of 933 patients and 327 catering staff. Patient satisfaction with the quality of hospital food and food-related service was evaluated by patient questionnaires. It was measured by assessing 14variables. Patients seem to be generally satisfied with the food served. In the regression analysis none of the influencing variables explained the component of 'patient satisfaction' at the level of P < 0.05, suggesting that it is a different kind of component from the other 4. Importantly the component 'patient satisfaction' appears to be explained predominantly by patients' own demographic and emotional variables rather than by objective catering system factors. Age and appetite were found to significantly correlate with patient satisfaction scores. The component of food waste was found to have a high negative correlation with patients' satisfaction. It may be possible to use food waste as an index of patient satisfaction in future research. Catering staff - satisfaction was evaluated by measuring employee job attitudes towards five aspects of their job using the Job Description Index (JDI). The JDI is directed toward specific areas of satisfaction rather than global or general satisfaction and was easily administered. The food service workers surveyed in this research were less satisfied with their jobs than are other types of workers in other industries. In the regression analysis total number of patients explains around 36% of the variation in staff satisfaction. The productivity level was based upon the total meal equivalents divided by the total labour hours required to produce and serve them. The regression analysis suggests that around 77% of the variance in productivity is explained by labour cost. The safety component was based upon two elements which were microbiological control and temperature control. The results of regression analysis suggest that the number of menu items and the subsidizing meal ratio explain around 74% of the variation in the safety component. Nutritional adequacy was evaluated indirectly by measurement of food waste. In the regression analysis more than 68% of food waste component can be explained by the variable occupancy rate. Correlations between the food quality components show that a non-significant relationship existed between all but one of the components of food quality studied. A significant negative correlation existed between the patients'satisfaction with the hospital meal and service and the food waste; this was expected. The non-significant correlations between the components of food quality showed the independence of components, confirming the need for a multi-dimensional model of food quality. The findings of this research support the notion that food quality is a multi-faceted phenomenon and have led to the development of a practical way of measuring it.
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Taylor, Tiffany M. J. "Effect of Antimicrobials and Sodium Replacement Agents on the Survival of Pathogenic Bacteria in Low Sodium Low-Moisture Part-Skim (LMPS) Mozzarella Cheese." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1102.
Full textAbstract:
Recent increases in chronic cardiovascular diseases, such as hypertension, have put pressure on the food industry to reduce sodium levels. Dairy products, though full of vital nutrients, are perceived as being high in sodium. However, the reduction of salt in dairy products could potentially alter the microbial stability, as well as cause unfavorable changes in flavor. In order to reduce the sodium level, while maintaining acceptable flavor and microbial stability, salt replacers and alternative antimicrobial agents may need to be introduced into the food matrix. To identify potential antimicrobials for use in reduced sodium dairy products, this study evaluated the efficacy of eight commercially available antimicrobials in TSA, milk agar, and cheese agar. Antimicrobials included MicroGard 100, MicroGard 430, Nisaplin, NovaGard CB1, Protect-M, PuraQ Verdad RV75, SEA-i F75 and VMY1P. Antimicrobials were also tested in combination with six commercial sodium reduction agents (potassium chloride, Puracal PP/USP, Purasal Hi Pure P Plus, PuraQ Verdad NV10, SaltWise 0029 and SaltWise 1029) to if there were any interference with antimicrobial activity.
Antimicrobials with and without sodium reduction agents were added to the agar systems, then a five-strain cocktail of Listeria monocytogenes, Salmonella or Escherichia coli O157:H7 was spread plated at three concentrations: 101, 102 and 104 CFU/plate. Samples were then incubated at 35°C and observed for growth after 24 and 48h. SEA-i F75 was the most effective antimicrobial in each of the agars tested. Additionally, no interactions were observed between SEA-i F75 and any of the sodium replacement agents.
SEA-i F75 was selected for use in a final challenge study using six formulations of LMPS mozzarella cheese: regular sodium control cheese (1.7% NaCl, no antimicrobial added); low sodium control cheese (0.7% NaCl, no antimicrobial added); low sodium treated cheese (0.7% NaCl, treatment with SEA-i F75); low sodium cheese with KCl as salt replacer (0.7% NaCl, 1.0% KCl, treatment with SEA-i F75); low sodium cheese with Alta 2345 as salt replacer (0.7% NaCl, 0.25% Alta 2345, treatment with SEA-i F75); and low sodium cheese with Salona as salt replacer (0.7% NaCl, 0.95% Salona, treatment with SEA-i F75).
Fifteen gram cheese pieces from each formulation were dipped in an antimicrobial solution containing 0.25% SEA-i F75 then inoculated with L. monocytogenes, Salmonella, or E. coli O157:H7 at a target inoculum concentration of 102-103 CFU/g and incubated at either 4° or 12°C. In all trials, over all formulations and temperatures tested, initial decreases in counts, followed by organism recovery were observed. Therefore, SEA-i F75 was not effective at reducing the counts of pathogenic bacteria in LMPS mozzarella cheese.
Results from this study highlight the effect of the food matrix, and its components on antimicrobial efficacy. Future research includes examining the effect of one of the other antimicrobials in LMPS mozzarella cheese.
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Lacy, Michael Pennington. "Peripheral regulation of food intake in the domestic fowl." Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/52301.
Full textAbstract:
Four studies were performed to examine peripheral factors involved with food intake regulation in the domestic fowl. In the first study, the mechanism by which tryptophan depresses food intake was clarified. Intraperitoneal injections of tryptophan methyl ester were demonstrated to inhibit feeding in Single Comb White Leghorn (SCWL) cockerels. Intragastric intubations of tryptophan inhibited food intake and decreased body temperature of SCWL cockerels. These results, in conjunction with previous findings, indicate that tryptophan's inhibitory influence on food intake is peripherally rather than centrally based. The second study explored the role of the duodenum in food intake regulation. Intraduodenal glucose loads had no effect on food intake of SCWL or Rock Cornish (RC) commercial broiler cockerels. In addition, splanchnicectomized birds did not respond to intraduodenal glucose infusions any differently than sham-operated controls. Apparently, the duodenum does not play a significant role in food intake control in the fowl. Hepatic involvement in appetite regulation was examined in SCWL and RC cockerels in the third study. Amino acid solutions failed to influence food intake when infused intraportally in either strain of chicken. Relatively small glucose or lipid solutions depressed food intake significantly when infused intraportally in the SCWL birds but had no effect in the RC cockerels. The liver appears to be integrally involved in controlling food consumption in the SCWL chicken. In the final study, the existence of a "hunger" factor in the peripheral circulation of two lines of chickens divergently selected for body weight was explored. Intrahepatic infusions of plasma from food deprived high-weight line chickens stimulated food intake of sated low-weight line chickens.
These studies indicate that peripheral mechanisms are important in regulating appetite in light-breed chickens such as the SCWL, however, such mechanisms in heavy-breed chickens such as the RC appear to be less sensitive. This desensitization in heavy-breed chickens suggests that genetic selection for increased growth has affected the food intake control systems.Ph. D.
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Docherty, Lorraine. "Molecular detection and gene expression of Campylobacter during stress conditions." Thesis, University of Surrey, 1997. http://epubs.surrey.ac.uk/843004/.
Full textAbstract:
The magnetic immuno-polymerase chain reaction assay (MIPA), was developed for the detection of Campylobacter jejuni and Campylobacter coli initially in milk and chicken products. After 18 hours pre-enrichment the MIPA could detect 420 cfu g-1 of chicken and 63 cfu ml-1 of artificially contaminated milk. MIPA was then applied for the detection of C. jejuni / C. coli in cloacal swabs and in retail poultry, where the sensitivity was found to be comparable to cultural methods. However, results were available significantly faster, within 24 hours compared to the 4-5 days of cultural methods. MIPA was also evaluated as a technique for the detection of "viable but non-culturable" (VBNC) forms in the environment. It was found that there was a reduction in sensitivity for the detection of these non-culturable forms (NCFs) and it was concluded that the MIPA had limited use in their detection. The lack of sensitivity of MIPA for detecting VBNC campylobacters in the environment may indicate that they are either antigenically or genetically distinct from the culturable forms. This result highlights the question of whether these VBNC forms actually represent a viable potentially infectious form of Campylobacter. This question can be answered at a molecular level; promoter activity can be monitored as a representation of viability of the bacterial cell during stress conditions. The promoter activity could be measured using a promoter probe vector. Initially we decided to construct a promoter probe vector which based on the recombinase system of the PI bacteriophage. However, the final construct was unstable and due to the constraints of time we decided to use a pre-existing promoter probe vector pSP73 constructed by Purdy and Park, (1993). This promoter probe vector contains promoterless luxAB genes which induce light emission as a reporter of gene expression. In order to investigate the genetic regulation during the conversion of C. jejuni to non-culturable forms (NCFs), we monitored gene expression during the transformation of C. jejuni into the non-culturable state. The promoterless copy of the luxAB genes was placed under the control of promoter regions of the C. jejuni flaA gene. Transformed C. jejuni was incubated under stress conditions that induce transition to NCFs (Non-culturable forms). Promoter activity, plate counts and direct microscope counts were simultaneously monitored. It was found that during the initial conversion of C. jejuni to NCFs there is an up-regulation of the flaA promoter. This regulation occurs in response to agitation and did not occur in NCFs and indicates that they are functionally non-viable.
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Mild, Rita Michelle. "Assessment of Campylobacter jejuni Loads in Feedlot Cattle and Poultry Environments and Post-Harvest." Diss., The University of Arizona, 2012. http://hdl.handle.net/10150/238649.
Full textAbstract:
Campylobacter jejuni is one of the most common causes of foodborne diarrheal illness in the U.S. and worldwide. (1-2). C. jejuni infection in humans is most often attributed to undercooked poultry (3-6). However, since 2001, the Centers for Disease Control (CDC) has confirmed 9 outbreaks of campylobacteriosis linked to consumption of beef and beef products, resulting in 297 illnesses and 10 hospitalizations, and cattle isolates have been linked to other human infections (7-10). Because Campylobacter infection is generally sporadic, and not all cases are linked to poultry, other animal reservoirs such as beef likely exist. Because beef is not commonly considered a significant source of Campylobacter, interventions regarding beef cattle are generally geared toward other pathogens, such as E. coli O157:H7. Interventions to prevent Campylobacter spread in poultry houses include reducing flock colonization and bacterial loads, (11), as well as interventions directly targeting consumer behavior. Despite these efforts, many countries have not been able to reduce the prevalence of Campylobacter in poultry. The goals of this research were to 1) determine Campylobacter loads in broilers at poultry farms and processing houses through the 3-tube MPN method, and determine baseline data for poultry production systems, 2) describe temporal relationships and prevalence of Campylobacter strains in a potentially underrepresented host/environment (cattle feedlot environment), and 3) test the efficacy of natural, plant derived compounds against C. jejuni on meat. Our results show that there is a significant positive association between pre-harvest and post-harvest Campylobacter loads in poultry, with Campylobacter levels during the final step of processing remaining at infectious levels. Beef cattle represent another potential and not well-described source of campylobacteriosis, as beef cattle and their environment become rapidly contaminated with Campylobacter from weaning through processing, and cross-contamination of carcasses is possible. This research also determined that natural plant extracts of cinnamon and oregano essential oils, when added to edible films, reduced surface contamination of retail poultry meat with C. jejuni, and thus may be a useful post-harvest intervention for future use in packaging of retail meat with a high risk of Campylobacter contamination.