The effects of selected antimicrobials, applied singularly or in combination, and frozen or refrigerated storage conditions on the survival of Listeria spp. on inoculated shrimp was evaluated in this study. A combination of 0.5% CPC (Cetylpyridinium Chloride) with a water wash at room temperature and freezing of the shrimp at -22.3 degrees C was the only treatment that had a significant antimicrobial effect on the Listeria spp. Antimicrobial effects and the mode of action of PEF (Pulsed Electric Field) and CPC on Listeria cells were evaluated in detailed studies. PEF in 0.1% sodium chloride had a bacterostatic effect toward Listeria spp. during refrigerated storage, but no immediate or bacteriostatic effect was caused by freezing the samples. A concentration of 1% sodium chloride reduced the Listeria spp. population after freezing by 1.1 log; however, the pungent chlorine odor that was generated during treatment might cause discomfort for employees in shrimp processing facilities. Also, chlorine might cause corrosion of metal surfaces of processing equipment. There was no difference in the antimicrobial effects on the survival of Listeria spp. by PEF between the exposure times of 1 or 2 min, as well as in the sodium chloride concentrations of 0.1 and 0.5%. PEF treatment in the presence of 0.1% sodium chloride is recommended. A solution of 0.5% CPC effectively inhibited all of the strains of Listeria spp. in the cell suspensions. A treatment of 0.5% CPC combined with PEF treatment in a sodium chloride concentration of 0.1% caused a delayed effect on the Listeria spp. after 2 d of refrigerated storage. After 2 d of frozen storage, the formation of ice crystals was decreased in the number of Listeria spp. when contaminated samples were treated with water. The results indicated chemicals (e.g. CPC and NaCl) might protect Listeria spp. from the formation of ice crystals. TEM (Transmission Electron Microscopy) micrographs revealed that cell membranes were damaged by PEF treatment and that cells were ruptured by CPC treatment. A maximum reduction of 2.76 log10 CFU/g of Listeria spp. on shrimp was achieved by a combination of PEFCPC.

A single tube detection kit was designed as a rapid, easy-to use and reliable test to detect Listeria spp.. Various food samples (vegetables and raw catfish fillets) were used in order to validate the performance of the detection kit. L. grayi was detected in one ready-to-eat (RTE) vegetables with the detection kit while no Listeria spp. was detected using the modified FDA-BAM method. In addition, both the detection kit and modified FDA-BAM method indicated that twelve catfish fillets were Listeria positive. The detection kit had 100% sensitivity and specificity in less detection time (24 h) than the modified FDA-BAM method (60% specificity, >72 h). There was no difference (P<0.05) between the kit and the modified FDA-BAM method on MPN for Listeria spp.

O queijo minas meia cura, popular entre os consumidores no Brasil, não é regulamentado, o que pressupõe que estes produtos sejam de origem informal, fabricados com leite cru, sem controle das condições higiênicas e sanitárias ou do processo de cura. Esta pesquisa se dispôs a estudar os fatores, tanto relacionados ao queijo (pH, Aw e U%) quanto aos relacionados à Listeria monocytogenes (análise qualitativa, quantitativa nas amostras que forem positiva e identificação e caracterização genotípica) como também pesquisar possível atividade antagônica das bactérias lácteas sobre a Listeria monocytogenes.Foram analisadas 165 amostras provindas de barracas de feiras do município de São Paulo. As análises físico-químicas classificaram as amostras como queijo de média umidade (57,6%) e de baixa umidade (34,5%); quanto ao pH, o valor mínimo registrado foi de 4,3 e o máximo foi de 7,5; e os valores da Aw variaram de 0,86 a 0,98. Listeria monocytogenes foi isolada em 3% das amostras (5/165) pelo método qualitativo, enquanto os testes de quantificação (feitos nas amostras positivas) não revelaram o agente, sugerindo que o nível de contaminação apresentava-se entre os limites de detecção das técnicas, a saber: 1 UFC/25g ou 0,04 UFC/g para a qualitativa e 3 NMP/g para a quantitativa . Em ambas as técnicas de caracterização genotípica (AFLP e PFGE) foram gerados cinco pulsotipos, cada um representando uma amostra. De 480 colônias isoladas das amostras, 6,66% apresentaram antagonismo pela L. monocytogenes. A freqüência de Listeria monocytogenes em queijo tipo minas meia cura é relativamente baixa e, quando presente, encontra-se em baixos níveis de contaminação. No entanto, do ponto de vista geográfico, o agente encontra-se no queijo tipo minas meia cura de todas as regiões do município de São Paulo. / Minas meia-cura cheese, popular among brazilian consumers, has not been regulated indicating that the cheese available in the market is informal and made from raw milk, uncontrolled hygienic-sanitary conditions nor the curing process. This study aimed evaluating factors related to the product (pH, Aw and U%) as well as the ones related to Listeria monocytogenes (qualitative analysis followed by quantitative analysis of the positive ones and genetic identification). Antagonic activity of some lactic bacteria against Listeria monocytogenes was also investigated. Samples (165) were bought at open markets in São Paulo city. By the content in humidity, samples were classified as cheese of medium (57,6%) and low humidity (34,5%); concerning pH the lowest value was 4,3 and the highest 7,5, values of Aw ranged from 0,86 a 0,98. Listeria monocytogenes was isolated from 3% of the samples (5/165) by qualitative test but none of them showed any growth in quantitative test suggesting that the level of contamination were somewhere in between the detection limits of the tests: 1 CFU/25 g or 0,04 CFU/g for qualitative method and 3 MPN/g for quantitative one. In both genotypic characterization techniques (AFLP and PFGE) five pulsotypes were generated, each one representing a sample. Of 480 colonies isolated from the samples, 6.66% showed antagonism by L. monocytogenes. The frequency of Listeria monocytogenes in Minas meia cura cheese is relatively low and when present the level of contamination is low. However it is wide distributed in Sao Paulo city.

O queijo minas meia cura, popular entre os consumidores no Brasil, não é regulamentado, o que pressupõe que estes produtos sejam de origem informal, fabricados com leite cru, sem controle das condições higiênicas e sanitárias ou do processo de cura. Esta pesquisa se dispôs a estudar os fatores, tanto relacionados ao queijo (pH, Aw e U%) quanto aos relacionados à Listeria monocytogenes (análise qualitativa, quantitativa nas amostras que forem positiva e identificação e caracterização genotípica) como também pesquisar possível atividade antagônica das bactérias lácteas sobre a Listeria monocytogenes.Foram analisadas 165 amostras provindas de barracas de feiras do município de São Paulo. As análises físico-químicas classificaram as amostras como queijo de média umidade (57,6%) e de baixa umidade (34,5%); quanto ao pH, o valor mínimo registrado foi de 4,3 e o máximo foi de 7,5; e os valores da Aw variaram de 0,86 a 0,98. Listeria monocytogenes foi isolada em 3% das amostras (5/165) pelo método qualitativo, enquanto os testes de quantificação (feitos nas amostras positivas) não revelaram o agente, sugerindo que o nível de contaminação apresentava-se entre os limites de detecção das técnicas, a saber: 1 UFC/25g ou 0,04 UFC/g para a qualitativa e 3 NMP/g para a quantitativa . Em ambas as técnicas de caracterização genotípica (AFLP e PFGE) foram gerados cinco pulsotipos, cada um representando uma amostra. De 480 colônias isoladas das amostras, 6,66% apresentaram antagonismo pela L. monocytogenes. A freqüência de Listeria monocytogenes em queijo tipo minas meia cura é relativamente baixa e, quando presente, encontra-se em baixos níveis de contaminação. No entanto, do ponto de vista geográfico, o agente encontra-se no queijo tipo minas meia cura de todas as regiões do município de São Paulo. / Minas meia-cura cheese, popular among brazilian consumers, has not been regulated indicating that the cheese available in the market is informal and made from raw milk, uncontrolled hygienic-sanitary conditions nor the curing process. This study aimed evaluating factors related to the product (pH, Aw and U%) as well as the ones related to Listeria monocytogenes (qualitative analysis followed by quantitative analysis of the positive ones and genetic identification). Antagonic activity of some lactic bacteria against Listeria monocytogenes was also investigated. Samples (165) were bought at open markets in São Paulo city. By the content in humidity, samples were classified as cheese of medium (57,6%) and low humidity (34,5%); concerning pH the lowest value was 4,3 and the highest 7,5, values of Aw ranged from 0,86 a 0,98. Listeria monocytogenes was isolated from 3% of the samples (5/165) by qualitative test but none of them showed any growth in quantitative test suggesting that the level of contamination were somewhere in between the detection limits of the tests: 1 CFU/25 g or 0,04 CFU/g for qualitative method and 3 MPN/g for quantitative one. In both genotypic characterization techniques (AFLP and PFGE) five pulsotypes were generated, each one representing a sample. Of 480 colonies isolated from the samples, 6.66% showed antagonism by L. monocytogenes. The frequency of Listeria monocytogenes in Minas meia cura cheese is relatively low and when present the level of contamination is low. However it is wide distributed in Sao Paulo city.

Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2018-03-19T13:47:26Z No. of bitstreams: 1 PGCA17MA224.pdf: 1064233 bytes, checksum: 031ba44fb55de3f4ff7bd6dc82539958 (MD5) / Made available in DSpace on 2018-03-19T13:47:26Z (GMT). No. of bitstreams: 1 PGCA17MA224.pdf: 1064233 bytes, checksum: 031ba44fb55de3f4ff7bd6dc82539958 (MD5) Previous issue date: 2017-02-24 / FUMDES / Listeriosis is a disease caused by bacteria of the genus Listeria spp, especially Listeria monocytogenes, the nervous form is the most important and frequent manifestation, characterized by a fatal meningoencephalitis, which mainly affects ruminants. We describe the epidemiological data, clinical signs and lesions of 27 outbreaks of listeriosis nerve in sheep and two in goats, diagnosed in the Laboratory of Animal Pathology (LAPA/CAV) between january 2007 and november 2015, in Santa Catarina. During this period, the disease occurred in the regions of Planalto Serrano, Alto Vale do Itajaí, North, Midwest, West and Florianópolis region. The animals affected were evaluated clinically and after worsening the clinical condition, were euthanized and necropsied with subsequent evaluation of macroscopic lesions, collection of viscera samples for histopathological examination and submission of refrigerated central nervous system samples for bacterial isolation. Silage samples from the properties where the outbreaks occurred were also sent with the same purpose. Sheep and goats presented clinical neurological signs such as incoordination, tournament, torticollis, salivation, protrusion and flaccidity of the tongue, unilateral palpebral, atrial and labial ptosis, as well as congestion of ocular mucosa and hyperthermia. The clinical condition varied from 5 to 10 days. All animals died even treated with antibiotics. At necropsy, small areas of dark and/or yellowish color were observed in the midbrain and hyperemia of the piamater. Histological lesions were characterized by perivascular mononuclear infiltrate and multifocal neutrophils in the central nervous system. The bacterial isolation was positive for the species Listeria monocytogenes, Listeria innocua, Listeria welshimeri and Listeria grayi / Listeriose é uma enfermidade provocada por bactérias do gênero Listeria spp, especialmente Listeria monocytogenes, sendo a forma nervosa a manifestação mais importante e frequente, caracterizada por um quadro de meningoencefalite fatal, que acomete principalmente ruminantes. Descrevem-se os dados epidemiológicos, sinais clínicos e lesões de 27 surtos de listeriose nervosa em ovinos e dois em caprinos, diagnosticados no Laboratório de Patologia Animal (LAPA/CAV) no período entre janeiro de 2007 a novembro de 2015, no estado de Santa Catarina. Durante este período, a doença ocorreu nas regiões do Planalto Serrano, Alto Vale do Itajaí, Norte, Oeste, Meio Oeste e Grande Florianópolis. Os animais acometidos foram avaliados clinicamente e após agravamento do quadro clínico, foram eutanasiados e necropsiados com posterior avaliação das lesões macroscópicas, coleta de amostras de vísceras para processamento histopatológico e envio de amostras refrigeradas de sistema nervoso central para isolamento bacteriano. Amostras de silagem provenientes das propriedades onde ocorreram os surtos também foram enviadas com a mesma finalidade. Os ovinos e caprinos apresentaram sinais clínicos neurológicos como incoordenação, torneio, torcicolo, salivação, protrusão e flacidez de língua, ptose palpebral, auricular e labial unilaterais, além de congestão de mucosa ocular e hipertermia. O quadro clínico variou de 5 a 10 dias. Todos os animais morreram mesmo tratados com antibióticos. Na necropsia foram observadas pequenas áreas de coloração escura e/ou amareladas no mesencéfalo e hiperemia da piamáter. As lesões histológicas foram caracterizadas por infiltrado mononuclear perivascular e de neutrófilos, multifocal, no sistema nervoso central. O isolamento bacteriano foi positivo para as espécies Listeria monocytogenes, Listeria innocua, Listeria welshimeri e Listeria grayi

Submitted by THAYSSA DUARTE COSTA null (thayssadc@uol.com.br) on 2016-03-14T20:30:14Z No. of bitstreams: 1 definitivo.pdf: 1376505 bytes, checksum: 3ea1cff27dcacca6fb6d638b154c38c1 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-03-15T13:25:34Z (GMT) No. of bitstreams: 1 costa_td_me_jabo.pdf: 1376505 bytes, checksum: 3ea1cff27dcacca6fb6d638b154c38c1 (MD5) / Made available in DSpace on 2016-03-15T13:25:34Z (GMT). No. of bitstreams: 1 costa_td_me_jabo.pdf: 1376505 bytes, checksum: 3ea1cff27dcacca6fb6d638b154c38c1 (MD5) Previous issue date: 2016-02-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A criação racional de peixes desempenha um importante papel na economia brasileira e a existência de áreas de lazer para a população acaba promovendo a pesca como uma atividade esportiva, recreativa ou de caráter cultural para a região. Porém, as negligências sanitárias nos pesque-pague aumenta a possibilidade de veiculação de doenças transmitidas pela ingestão desses peixes. Há ainda a preocupação quanto aos antimicrobianos, pois o uso indiscriminado e/ou errôneo destes favorece a seleção de micro-organismos resistentes. Com base nos fatos mencionados o presente estudo teve como objetivo avaliar a qualidade microbiológica e verificar o perfil de sensibilidade antimicrobiana dos isolados de tilápia (Oreochromis spp.) oriundas de pesqueiros da microrregião centro-leste do Estado de São Paulo, Brasil. Para tanto, verificou-se o atendimento as exigências microbiológicas da legislação vigente - RDC n°12/ANVISA - para pescado fresco (peixe inteiro e filés), além da enumeração de coliformes termotolerantes e verificação da presença de Listeria spp., bem como avaliar a sensibilidade antimicrobiana dos isolados. Foram realizadas nove colheitas, quinzenalmente, em dois pesque-pague (Azul e Vermelho) e após o abate e filetagem no próprio estabelecimento, os 18 peixes inteiros e os 18 filés foram transportados para o laboratório para análises, durante o período de setembro/2014 a fevereiro/2015. Os resultados mostraram que, de acordo com a legislação vigente, apenas 11 (30,55%) amostras atendem ao estabelecido, sendo as amostras de filé apenas 4 (22,23%) obtidas do pesque-pague Azul e 3 (16,67%) do Vermelho seriam consideradas próprias para o consumo; já para amostras de peixe inteiro, nenhuma do pesque pague Azul estava apta para o consumo e do pesque-pague Vermelho 4 (22,23%) estariam aptas. O número mais provável de coliformes termotolerantes variou de <0,3x10(0) a 1,1x10(3) NMP.g(-1) nos filés e 0,9x10(0) a >1,1x10(3) NMP.mL(-1) nos peixes inteiros. Foram encontrados nas amostras 13 (36,12%) isolados de Listeria spp., sendo 6 (46,15%) dos filés e 7 (53,85%) dos peixes inteiros; e a confirmação da presença de Listeria monocytogenes ocorreu em 2 (15,38%) filés e 3 (23,07%) peixes inteiros. Dos cinco antibióticos testados em comum com o grupo de isolados estudados, a ciprofloxacina e a gentamicina se destacaram no controle dos Gram-negativos, enquanto que a ciprofloxacina, o florfenicol e a tetraciclina se destacaram nos Gram-positivos. Os dados levantados servem de alerta às autoridades, visto que houve a presença de micro-organismos cotados pela legislação e presença de patógenos nas amostras, além de resistência a antimicrobianos usados tanto na veterinária quanto na medicina humana, demonstrando necessidade de fiscalização nos locais. / The creation of fish plays an important role in the brazilian economy and the existence of recreational areas for the population ends up promoting fishing as a sport activity, recreational or cultural character to the region. However, health oversights in fish-pay increases the possibility of airing of diseases transmitted by ingestion of these fish. On the basis of the facts mentioned, this study aimed to assess the microbiological quality and check the profile of antimicrobial sensitivity of isolated from tilapia (Oreochromis spp.) from fishing grounds of east-central microregion of the State of São Paulo in Brazil. For both, it was found the microbiological requirements of care legislation - RDC n° 12 ANVISA - for fresh fish (whole fish and fillets), in addition to the enumeration of coliforms termotolerantes and checking for the presence of Listeria spp., as well as assess the antimicrobial sensitivity of isolated. Nine crops were held, biweekly, in two fish-pay (Blue and Red) and after slaughter and filleting at the establishment, the 18 whole fish and fillets 18 were transported to the laboratory for analysis during the period of setembro/2014 since fevereiro/2015. The results showed that, in accordance with the current legislation, only 11 (30.55%) samples meet the established, being the only fillet samples 4 (22.23%) obtained from Blue fish-pay and 3 (16.67%) of Red would be considered fit for consumption; to whole fish samples, none of the net pay was fit for consumption Blue and the Red fish-pay 4 (22.23%) would be suitable. The most probable number of coliform termotolerantes ranged from <0,3x10(0) to 1,1x10(3) MNP.g(-1) in fillets and 0,9x10(0) to >1,1x10(3) NMP.mL(-1) in the whole fish. Were found in samples 13 (36.12%) isolates of Listeria spp., being 6 (46.15%) of fillets and 7 (53.85%) of whole fish; and the confirmation of the presence of Listeria monocytogenes occurred in 2 (15.38%) fillets and whole fish 3 (23.07%). Of the five antibiotics tested in common with the group of isolates studied, ciprofloxacin and gentamicin stood out in the control of Gram-negative, while the ciprofloxacin, florfenicol and tetracycline have excelled in Gram-positives. The data collected serve to alert the authorities, since the presence of micro-organisms listed by the law, and the presence of pathogens in samples, in addition to antimicrobial resistance used in veterinary medicine as in human medicine, demonstrating the need for monitoring in places.

Made available in DSpace on 2014-08-20T13:42:06Z (GMT). No. of bitstreams: 1 Denise da Fontoura Prates.pdf: 535436 bytes, checksum: c3acb08e8f12a05440096b13c688b6f2 (MD5) Previous issue date: 2010-12-17 / Listeria monocytogenes is a Gram-positive of ubiquitous natural, psychrotropic pathogen which colonizes the surfaces of equipment and utensils in food processing industries. Milk and dairy products, especially cheeses with medium and high humidity have been implicated in listeriosis cases and outbreaks. Microbial contamination could be originated in raw material or be incorporated during the development stages of the product, coupled with inadequate hygiene practices. The general aim of this study was to evaluate the occurrence of Listeria spp. along the processing line of cheese with middle and high humidity, in three dairy subjected to different levels of sanitary survey located in Southern Brazil. From 208 samples tested Listeria spp. were isolated 7.69%, being isolated 43.75%, 25%, 31.25%, respectively, in dairy products A, B and C. From these isolates, 25% were found in raw milk, 18.75% in contact surfaces with the product, 50% in areas without contact with the product and 6.25% in the final product. L. innocua and L. monocytogenes were the only species identified between the isolates being L. innocua the prevalent species (68.7%). Among the serotypes of L. innocua, the serotype 6a was prevalent (72.7%) and between L. monocytogenes serotype 4b was prevalent (55.6%). All Listeria strains isolated from raw material and final product showed multiresistance to five antibiotics (penicillin, amoxicillin, chloramphenicol, cefaclor and clindamycin) of the fifteen antibiotics tested. Among the samples of raw material assessed microbiologically, the raw milk showed the highest levels of contamination and the highest levels found between them were > 1.1x106 MPN/mL for fecal Overall, 1.1x105 MPN/mL for fecal coliform, 4x105 CFU/ml for coagulase-positive staphylococci and Salmonella spp. in one of the samples. Among six samples of the final product, only one showed himself at odds with the existing regulatory standard, exceeding the allowed limit for ECP. Listeria spp. and L. monocytogenes were present along the lines of the three dairy processing plants, regardless of the size of the industry, highlighting the risk of contamination during food manufacturing. Therefore, it becomes necessary to introduce effective measures to reduce such contamination or improvements in the practices already adopted by the industry, because of the risks to public health. / Listeria monocytogenes é uma bactéria Gram-positiva de natureza ubíqua, psicrotrófica, que coloniza superfícies de equipamentos e utensílios dentro de indústrias processadoras de alimentos. Leites e derivados lácteos, em especial queijos com média e alta umidade, têm sido incriminados em casos e surtos de listeriose, por serem alimentos que favorecem o desenvolvimento microbiano, além de serem prontos para o consumo. A contaminação microbiana pode ter origem na matéria-prima, ou ser incorporada durante as etapas de elaboração do produto, associada a práticas inadequadas de higiene. O objetivo geral neste trabalho foi avaliar a ocorrência de Listeria spp., em especial de L. monocytogenes, ao longo da linha de processamento de queijos de média e alta umidade, em três laticínios, localizados na região sul do Rio Grande do Sul, submetidos a diferentes níveis de inspeção sanitária. Das 208 amostras avaliadas 7,69% apresentaram Listeria spp., sendo isoladas, 43,75%, 25%, 31,25%, respectivamente, nos laticínios A, B e C. Destes isolados, 25% foram encontrados no leite cru, 18,75% em superfícies de contato com o produto, 50% em superfícies sem contato com o produto e 6,25% no produto final. L. innocua e L. monocytogenes foram as únicas espécies identificadas entre os isolados, sendo L. innocua a espécie prevalente (68,7%). Entre os sorotipos de L. innocua, o prevalente foi 6a (72,7%) e entre L. monocytogenes o sorotipo prevalente foi 4b (55,6%). Todas as cepas de Listeria isoladas da matéria-prima e do produto final apresentaram multirresistência a cinco (penicilina, amoxilina, cloranfenicol, cefaclor e clindamicina) dos 15 antibióticos testados. Dentre as amostras de matéria-prima avaliadas microbiologicamente, as de leite cru, foram as que apresentaram os maiores níveis de contaminação, sendo que, os níveis mais elevados encontrados entre as amostras de leite cru foram: >1,1x106 NMP.mL-1 para coliformes totais, 1,1x105 NMP.mL-1 para coliformes termotolerantes, 4x105 UFC.mL-1 para estafilococos coagulase positiva (ECP) e a presença de Salmonella spp. em uma das amostras avaliadas. Entre as seis amostras de produto final, apenas uma apresentou-se em desacordo com o padrão regulamentar vigente, excedendo o limite permitido para ECP. Listeria spp. e L. monocytogenes foram isoladas ao longo das linhas de processamentos nos três laticínios, independente do porte da indústria, evidenciando risco de contaminação durante a fabricação dos dois tipos de queijo, os quais são produtos prontos para o consumo. Dessa forma, torna-se necessária a implantação de medidas eficazes para redução dessas contaminações, ou melhorias nas práticas já adotadas pelas indústrias, em virtude dos riscos à saúde pública.

Prior research has shown pathogen prevalence on-farms is not uniformly distributed, instead pathogen prevalence is highly dependent on environmental factors and management practices. A study was performed to determine environmental factors (e.g., landscape features, meteorological events) and management practices (e.g., date of last irrigation, pesticide application) that may impact the prevalence of Salmonella spp. and Listeria spp. at the sub-field level (0.2 ha grids) on an Eastern Shore of Virginia farm. Virginia Tech's Eastern Shore Agricultural Research and Extension Center (ESAREC) farm was used due to the liability of testing for pathogens in commercial produce fields; however, production practices used at the ESAREC farm are similar, if not the same, to production practices used on commercial farms. Fifteen drag swab, one water, and up to five fecal samples were collected every two weeks per sampling occurrence from August to December 2016 (thus up to 21 samples may be collected during one sampling occurrence. Samples were collected from randomized field plots that were picked during each sampling occurrence. Salmonella spp. and Listeria spp. were isolated and confirmed using modified versions of the Food and Drug Administration's Bacteriological Analytical Manual. Environmental factors were retrieved by remotely-sensed data for the sample location or date. Management practices were recorded by an observational survey for each sample occurrence. Two hundred and seventy-four samples (210 drag swab, 50 fecal, and 14 water samples) were collected during the late summer, fall, and winter. Listeria spp. and Salmonella spp. was detected in 8.3% (23/274) and 1.8% (5/274) of samples, respectively. Neither pathogen was detected in any of the fourteen water samples tested. Findings from this study will support the development of mitigation strategies to reduce pathogen contamination on-farm, with emphasis at the sub-field level. For instance, mitigation strategies include growers electing to not harvest near edges of fields or directly after precipitation events to minimize contamination events. Additionally, management practices were found to be associated with pathogen prevalence; therefore, management practices should be carefully tailored for each unique farm landscape. / Master of Science in Life Sciences / Over the years, fresh produce consumption has been on the rise and the concern with the safety of fresh produce has been the focus of recent studies. Raw produce has been recognized to be a potential source of pathogens that has caused human foodborne illness. Foodborne illnesses are caused by pathogens such as Listeria monocytogenes and Salmonella spp. just to mention a few. It is essential to minimize potential contamination of products with no kill step including fruits and vegetables during the whole supply chain (farm to fork). A study of environmental factors and management practices was performed to determine the influence that the factors have on pathogen prevalence of Salmonella spp. and Listeria spp. at the sub field level. As well as develop mitigation strategies to minimize contamination of produce on-farm. Over the span of 8 months, environmental samples were collected from drag swabs, fecal, and pond water used for irrigation on the farm. Management and environmental factors were recorded during every sampling occasion. Samples where then processed for the selection of Salmonella and Listeria species. Historically, it has been noted that seasons play a role in pathogen prevalence. Amongst all the samples collected during the study the prevalence for Salmonella spp. was 1.8% and Listeria spp. was 8.3% Salmonella spp. and Listeria spp. recovery was performed by following the guidelines of the Food and Drug Administration Bacteriological Analytical Manual. Factors such as seasonality, cover crop use, and irrigation use were shown to have an effect on the likelihood of detecting a pathogen positive. Any of the three factors listed were shown to be associated with an increased pathogen prevalence. By identifying these factors, growers may develop targeted mitigation strategies to reduce pathogen contamination in the pre-harvest environment.

O presente trabalho teve como objetivo avaliar o tempo necessário para que carcaças de frango de diferentes pesos (1.200 g e 2.100g), que ao sair do tanque de resfriamento se encontravam com a temperatura acima de 7ºC, alcançassem 4°C e traçar o perfil microbiológico destas, realizado através do estudo de presença e multiplicação dos indicadores: microrganismos mesófilos aeróbios, coliformes totais, coliformes termotolerantes, Escherichia coli, Staphylococcus coagulase positivo, Clostridium perfringens, Salmonella spp. e Listeria spp. a fim de auxiliar as medidas e os limites críticos de um plano APPCC para a indústria de carne de ave. A pesquisa foi realizada em um matadouro localizado no Estado do Rio Grande do Sul. No total foram coletadas aleatoriamente 100 carcaças de frangos, 50 amostras para cada peso, com temperatura acima de 7°C, na esteira na saída dos tanques de resfriamento. Todas as carcaças foram colocadas em caixa plásticas e encaminhadas à câmara de resfriamento (tempo zero). De hora em hora foi realizada a aferição de temperatura no músculo peitoral profundo de 15 unidades amostrais de cada peso. As carcaças com peso de 1.200 g levaram de 2 a 4 horas para alcançarem a temperatura de 4ºC na musculatura profunda e as carcaças com peso médio de 2.100 g, chegaram a temperatura de 4ºC entre 5 e 8 horas de resfriamento. No momento da coleta das amostras e a cada hora, foram coletadas 5 unidades amostrais, de cada grupo, para análise microbiológica, totalizando 25 amostras para carcaças de frango de 1.200 g e 43 amostras para carcaças de frango de 2.100 g. A contagem de bactérias mesófilas aeróbias não apresentou declínio significativo (P> 0,05) ao longo do tempo de resfriamento, tanto em carcaças de 1.200 g quanto nas carcaças com peso de 2.100 g. A contagem de Staphylococcus coagulase positivo manteve-se, durante todo o experimento, para os dois tipos de amostras (1.200 e 2.100 g) dentro do limite estipulado pela legislação, todos os frangos analisados apresentaram resultados menores que 2,0 log10 UFC/g. Não houve o crescimento de Clostridium perfringens em nenhuma das análises realizadas, tanto em carcaças de frango com 1.200 g quanto naquelas com 2.100g. Para coliformes totais, a queda da temperatura foi significativa no declínio da contagem microbiana somente para carcaças de 2.100g. Já para coliformes termotolerantes e E. coli foi possível identificar declínio na contagem bacteriana ao longo do tempo de resfriamento para carcaças de 1.200g e para carcaças de 2.100g (P 0,05). Foi observada a presença de Salmonella spp. e Listeria spp. em temperaturas de refrigeração. Para carcaças de 1.200g, foi isolado Salmonella spp. em uma amostra que se encontrava na temperatura de 4,6°C e, em uma amostra, para carcaças de 2.100g, que se encontrava na temperatura de 7,2°C. Listeria spp. apenas foi detectada em carcaças de 2.100g, sendo uma amostra com temperatura de 6,2°C e em 04 amostras com temperatura de 4,6°. Verificou-se correlação inversa entre temperatura da carcaça e presença do microrganismo, isto é, a detecção de Listeria spp. ocorreu quando houve a queda da temperatura, isolando-a em temperaturas de refrigeração. / The present work aimed to evaluating the time necessary for broiler meat of different weights (1.200g e 2.100g, that after chiller had the temperature over 7°C), to be raised 4°C in temperature and to perform a microbiological profile through the study of the presence of indicators (mesophilic aerobes pathogens, total coliform, thermotolerant coliform, Escherichia coli, Staphylococcus coagulase positive, Clostridium perfringens, Salmonella spp. e Listeria spp.) and their multiplication, in order to help measuring critical limits in a HACCP plan to be applied to a broiler meat industry. The research was performed in a slaughterhouse located in the State of Rio Grande do Sul, Southern Brazil. One hundred broiler carcasses were collected, being 50 samples of each weight (1.200g e 2.100g), which showed temperatures above 7°C, at the end of the chiller. All carcasses were put in plastic boxes and placed in a freezing chamber (time zero). The temperature was then measured every hour in the profound pectoral muscle of 15 samples of each weight. The carcasses weighting 1.200g took 2 to 4 hours to raise 4°C in the profound musculature while the carcasses weighting 2.100g raised 4°C in 5 to 8 hours of freezing. The counting of mesophilic microorganisms did not show any significant reduction (P>0,05) during the freezing period, for both carcasses with 1.200g and the ones with 2.100g. The counting of coagulase positive Staphylococcus maintained, during the whole experiment, within the legislation limits, with all samples showing results below 2,0 log10 UFC/g. The study did not show any growth of Clostridium perfringens in all the samples collected. Regarding total coliforms, the temperature reduction was significantly connected to the reduction of bacterial counting in carcasses with 2.100g. On the other hand, in terms of thermotolerant coliform and E. coli, it was possible to detect a reduction of bacterial counting during the freezing time in carcasses of 1.200g as well as 2.100g (P 0,05). The presence of Salmonella spp. and Listeria spp. in refrigeration temperatures were also observed. In carcasses with 1.200g, Salmonella spp. was isolated in one sample in the temperature of 4,6°C and also in carcasses with 2.100g, in one sample that was in the temperature of 7,2°C. Listeria spp. was only detected in carcasses with 2.100g in one sample with the temperature 6,2°C and in four samples with temperature 4,6°C. A negative correlation between carcass temperature and microorganism presence was detected, that is, the detection of Listeria spp. occurred at refrigeration temperatures, when the temperature was reduced.

O presente trabalho teve como objetivo avaliar o tempo necessário para que carcaças de frango de diferentes pesos (1.200 g e 2.100g), que ao sair do tanque de resfriamento se encontravam com a temperatura acima de 7ºC, alcançassem 4°C e traçar o perfil microbiológico destas, realizado através do estudo de presença e multiplicação dos indicadores: microrganismos mesófilos aeróbios, coliformes totais, coliformes termotolerantes, Escherichia coli, Staphylococcus coagulase positivo, Clostridium perfringens, Salmonella spp. e Listeria spp. a fim de auxiliar as medidas e os limites críticos de um plano APPCC para a indústria de carne de ave. A pesquisa foi realizada em um matadouro localizado no Estado do Rio Grande do Sul. No total foram coletadas aleatoriamente 100 carcaças de frangos, 50 amostras para cada peso, com temperatura acima de 7°C, na esteira na saída dos tanques de resfriamento. Todas as carcaças foram colocadas em caixa plásticas e encaminhadas à câmara de resfriamento (tempo zero). De hora em hora foi realizada a aferição de temperatura no músculo peitoral profundo de 15 unidades amostrais de cada peso. As carcaças com peso de 1.200 g levaram de 2 a 4 horas para alcançarem a temperatura de 4ºC na musculatura profunda e as carcaças com peso médio de 2.100 g, chegaram a temperatura de 4ºC entre 5 e 8 horas de resfriamento. No momento da coleta das amostras e a cada hora, foram coletadas 5 unidades amostrais, de cada grupo, para análise microbiológica, totalizando 25 amostras para carcaças de frango de 1.200 g e 43 amostras para carcaças de frango de 2.100 g. A contagem de bactérias mesófilas aeróbias não apresentou declínio significativo (P> 0,05) ao longo do tempo de resfriamento, tanto em carcaças de 1.200 g quanto nas carcaças com peso de 2.100 g. A contagem de Staphylococcus coagulase positivo manteve-se, durante todo o experimento, para os dois tipos de amostras (1.200 e 2.100 g) dentro do limite estipulado pela legislação, todos os frangos analisados apresentaram resultados menores que 2,0 log10 UFC/g. Não houve o crescimento de Clostridium perfringens em nenhuma das análises realizadas, tanto em carcaças de frango com 1.200 g quanto naquelas com 2.100g. Para coliformes totais, a queda da temperatura foi significativa no declínio da contagem microbiana somente para carcaças de 2.100g. Já para coliformes termotolerantes e E. coli foi possível identificar declínio na contagem bacteriana ao longo do tempo de resfriamento para carcaças de 1.200g e para carcaças de 2.100g (P 0,05). Foi observada a presença de Salmonella spp. e Listeria spp. em temperaturas de refrigeração. Para carcaças de 1.200g, foi isolado Salmonella spp. em uma amostra que se encontrava na temperatura de 4,6°C e, em uma amostra, para carcaças de 2.100g, que se encontrava na temperatura de 7,2°C. Listeria spp. apenas foi detectada em carcaças de 2.100g, sendo uma amostra com temperatura de 6,2°C e em 04 amostras com temperatura de 4,6°. Verificou-se correlação inversa entre temperatura da carcaça e presença do microrganismo, isto é, a detecção de Listeria spp. ocorreu quando houve a queda da temperatura, isolando-a em temperaturas de refrigeração. / The present work aimed to evaluating the time necessary for broiler meat of different weights (1.200g e 2.100g, that after chiller had the temperature over 7°C), to be raised 4°C in temperature and to perform a microbiological profile through the study of the presence of indicators (mesophilic aerobes pathogens, total coliform, thermotolerant coliform, Escherichia coli, Staphylococcus coagulase positive, Clostridium perfringens, Salmonella spp. e Listeria spp.) and their multiplication, in order to help measuring critical limits in a HACCP plan to be applied to a broiler meat industry. The research was performed in a slaughterhouse located in the State of Rio Grande do Sul, Southern Brazil. One hundred broiler carcasses were collected, being 50 samples of each weight (1.200g e 2.100g), which showed temperatures above 7°C, at the end of the chiller. All carcasses were put in plastic boxes and placed in a freezing chamber (time zero). The temperature was then measured every hour in the profound pectoral muscle of 15 samples of each weight. The carcasses weighting 1.200g took 2 to 4 hours to raise 4°C in the profound musculature while the carcasses weighting 2.100g raised 4°C in 5 to 8 hours of freezing. The counting of mesophilic microorganisms did not show any significant reduction (P>0,05) during the freezing period, for both carcasses with 1.200g and the ones with 2.100g. The counting of coagulase positive Staphylococcus maintained, during the whole experiment, within the legislation limits, with all samples showing results below 2,0 log10 UFC/g. The study did not show any growth of Clostridium perfringens in all the samples collected. Regarding total coliforms, the temperature reduction was significantly connected to the reduction of bacterial counting in carcasses with 2.100g. On the other hand, in terms of thermotolerant coliform and E. coli, it was possible to detect a reduction of bacterial counting during the freezing time in carcasses of 1.200g as well as 2.100g (P 0,05). The presence of Salmonella spp. and Listeria spp. in refrigeration temperatures were also observed. In carcasses with 1.200g, Salmonella spp. was isolated in one sample in the temperature of 4,6°C and also in carcasses with 2.100g, in one sample that was in the temperature of 7,2°C. Listeria spp. was only detected in carcasses with 2.100g in one sample with the temperature 6,2°C and in four samples with temperature 4,6°C. A negative correlation between carcass temperature and microorganism presence was detected, that is, the detection of Listeria spp. occurred at refrigeration temperatures, when the temperature was reduced.