Resistência a antimicrobianos de amostras de Escherichia coli isoladas de esterqueiras para o tratamento de dejetos suínos

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Caracterização da microbiota mesófila aeróbia isolada de um sistema de lagoas de estabilização para o tratamento de dejetos de suínos

O comportamento de populações microbianas mesófilas, presentes em dejetos suínos submetidos a tratamento em lagoas de estabilização, ainda é pouco conhecido. O objetivo deste estudo foi avaliar a variação quantitativa e qualitativa da microbiota mesófila aeróbia presente ao longo de um sistema de lagoas de estabilização para tratamento de dejetos suínos. A população média de mesófilos aeróbios manteve-se constante ao longo das lagoas, apesar de ter havido uma variação nas contagens entre as diferentes coletas realizadas. A diversidade média da microbiota do efluente foi menor que a encontrada no afluente do sistema, não havendo diferença na equitabilidade entre os pontos amostrados. No início do sistema houve um predomínio de bactérias com características compatíveis com as enterobactérias, enquanto no efluente predominaram grupos semelhantes aos enterococos

Isolamento de Salmonella Typhimurium, Listeria monocytogenes e Staphylococcus coagulase positiva de salames comercializados em feiras livres de Porto Alegre, Brasil

Salami is a ready-to-eat (RTE) product frequently purchased at street fairs in Porto Alegre. Salmonella enterica, Listeria monocytogenes, and coagulase-positive Staphylococcus (CPS) are important causes of foodborne disease and can be transmitted through the consumption of RTE foods. The aim of this study was to evaluate the presence of these pathogens in salami sold at street fairs. Ninety salami samples from three commercial brands available at street fairs were analyzed by routine bacteriological methods for Salmonella spp. and Listeria spp., as well as enumeration of CPS. In addition, two samples from each commercial brand were analyzed for water activity (aw). Samples of brand A showed aw values (0.938 and 0.942) above those set by the legislation, while brand B (0.849 and 0.860) and brand C (0.826 and 0.854) were compliant. Microbiological analyses showed that 67.7% were negative to all investigated bacteria. Salmonella Typhimurium was isolated from 4.4% (4/90) of salami samples, all from commercial brand A. Listeria monocytogenes was detected in 3.3% (3/90) of samples, from commercial brands B and C. Moreover, 7.7% (7/90) of samples contained CPS populations non-compliant with legislation. Although the great majority of salami sold at street fairs of Porto Alegre was compliant with standards, S. enterica, L. monocytogenes, and CPS ≥ 5 × 103 cfu.g-1 could be found in this RTE product. Therefore, control measures in the processing industry and consumer’s education about foodborne illness prevention should be maintained.Salame é um alimento pronto para o consumo frequentemente adquirido pela população em feiras livres de Porto Alegre. Salmonella enterica, Listeria monocytogenes e Staphylococcus coagulase positiva são importantes causas de doenças transmitidas por alimentos e podem ser veiculadas por alimentos prontos para o consumo. O objetivo desse estudo foi avaliar a presença desses patógenos em salames vendidos em feiras livres. Noventa amostras de salame pertencentes a três marcas comerciais foram analisados por métodos bacteriológicos de rotina quanto à presença de Salmonella spp. e Listeria spp., bem como enumeração de Staphylococcus coagulase positiva (SCP). Além disso, foi determinada a Atividade de Água (aw) de duas amostras de cada marca comercial. Amostras da marca A apresentaram valores de aw (0,938 e 0,942) acima do permitido na legislação, enquanto as amostras da marca B (0,849 e 0,860) e C (0,826 e 0,854) não violaram esse parâmetro. A análise microbiológica demonstrou que 67,7% das amostras foram negativas para todas as bactérias investigadas. Salmonella Typhimurium foi isolada de 4,4% (4/90) das amostras de salame, todas da marca comercial A. Listeria monocytogenes foi detectada em 3,3% (3/90) das amostras das marcas B e C. Além disso, 7,7% (7/90) das amostras apresentaram SCP acima do número permitido pela legislação. Apesar da grande maioria dos salames comercializados em feiras livres estarem de acordo com a legislação, S. enterica, L. monocytogenes e SCP ≥ 5 × 103 cfu.g-1 podem estar presentes nesse alimento pronto para o consumo. Dessa forma, o controle nas indústrias e a educação dos consumidores sobre a prevenção de doenças transmitidas por alimentos devem ser mantidos

Pesquisa de aglutininas anti-leptospira em cães clinicamente sadios e com suspeita clínica de leptospirose

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Antimicrobial resistance profile of bacteria isolated from canine and feline samples at the Preventive Veterinary Laboratory of the Federal University of Rio Grande do Sul (UFRGS) – Brazil

Background: Antimicrobial resistance (AMR) is a major global health threat. In small animals such as dogs and cats, antimicrobials are most commonly prescribed for skin and genitourinary diseases; therefore, the AMR of bacteria involved in these infections should be monitored. In addition, the results of antimicrobial susceptibility testing (AST) may be interpreted as a local epidemiological history of AMR. The Preventive Veterinary Medicine Laboratory (PVML) received clinical samples from dogs and cats for bacterial isolation and AST. Thus, this study aimed to assess the AMR of bacteria isolated from the samples of dogs and cats received at the Preventive Veterinary Medicine Laboratory (PVML). Materials, Methods & Results: Data from bacteriological examinations performed at the PVML of the Universidade Federal do Rio Grande do Sul (UFRGS) during 5 years were analyzed. Skin and ear canal samples were inoculated in 5% sheep blood agar, and urine samples were streaked on CHROMagar™ orientation. After incubation at 36±1°C for up to 72 h, identification and AST were performed according to routine protocols. Of 1,534 samples submitted to the PVML, 1,086 (70.8%) were collected from dogs and 29.2% from feline patients. Otological swabs (n = 533, 49.1%) were the most frequent samples from dogs, while cat urine samples (n = 384, 84.8%) predominated by far. Considering the canine samples, no bacterial growth (NBG) was observed in 443 (40.8%) samples, while only one colony type was noted in 516 (47.5%) samples. Gram-positive bacteria (n = 298) were more frequent than gram-negative bacteria (n = 77) in the skin. In urine samples, gram-negative bacteria (n = 94) were isolated more frequently than gram-positive bacteria (n = 47). In feline samples, a high number of NBG (n = 308, 68%) was observed. Gram-positive (n = 22) was predominant in comparison to gram-negative bacteria (n = 9) in cultures from the ear and skin swabs. Enterococcus spp. and Escherichia coli were the most frequently identified bacteria in urine samples. Among the Staphylococcus sp. strains of any origin, AMR frequency varied from 4.22% (amikacin) to 50.70% (sulfa/trimethoprim). Enterococcus spp. showed AMR frequencies from 12.5% (amoxicillin/clavulanic acid) to 62.06% (enrofloxacin). Among the gram-negative genera, E. coli presented AMR frequencies from 10.20% (gentamicin) to 60.0% (neomycin). The frequency of AMR was stable over time, and a profile of much higher resistance to fluoroquinolones in comparison to beta-lactams was observed. Discussion: The recurrence of skin and urinary infections implies the need for frequent treatment with antibiotics, which exerts selection pressure for resistance and multidrug resistance. In this study, the frequency of multidrug resistance was low, and the resistance to the tested antimicrobials showed high variation. However, a trend of high resistance to the fluoroquinolone group was observed in contrast to the low resistance to beta-lactams. This trend was consistent among the isolated bacteria, regardless of the type of sample or origin. The overprescription of fluoroquinolones in small animal practices has been widely documented in several countries. However, this class of antimicrobials, is highly prioritized for the treatment of infections in humans. Therefore, the selection of resistant strains has gained special emphasis, especially when considering the possibility of the transmission of resistant bacteria between pets and humans. In summary, the results of bacteriological tests conducted at the PVML-Universidade Federal do Rio Grande do Sul confirmed that ubiquitous bacteria predominate in clinical samples of dogs and cats. The high frequency of resistance to the fluoroquinolone group, while a predominance of susceptible strains in the first-choice drugs such as amoxicillin/clavulanic acid, may indicate excessive and empirical use of the second-choice drugs in clinical practice

Avaliação da sobrevivência de Salmonella enterica inoculada em salame de carne suína

Pork salami is an embedded, cured and ripened product commonly consumed in Brazil, and the presence of Salmonella enterica has already been reported in this product. During its preparation, the microbiological safety depends on the meat quality, addition of ingredients with antimicrobial activity, hygiene during processing, pH and water activity (Aw) reduction during maturation. In Brazil, the maturation protocol has not been determined in food regulation; therefore, the objectives of this study were (a) to identify the fermentation and drying phases during salami maturation; (b) to test the survival of S. enterica during salami processing; and (c) to compare xylose lysine deoxycholate (XLD) and thin agar layer (TAL) agar for recovering Salmonella. The salami samples were prepared with a cocktail of S. enterica strains, fermented at 30°C and dried at 20°C with controlled relative humidity (RH). Periodic sampling for S. enterica quantification and Aw and pH analyses were performed during maturation, and curves were constructed. Fermentation occurred during the first 66 hours, and the pH decreased while the population of S. enterica increased over the first 21 hours. The drying step was able to reduce the bacterial population by approximately 5 log CFU after 875 hours, reaching an Aw of less than 0.78. However, elimination of S. enterica was not achieved. For Salmonella recovery, TAL agar was more efficient than XLD agar.O salame de carne suína é um produto embutido, curado e maturado comumente consumido no Brasil no qual a presença de Salmonella enterica tem sido relatada. Durante a sua elaboração, a segurança microbiológica depende da qualidade da carne, adição de ingredientes com atividade antimicrobiana, higiene durante a produção, redução de pH e atividade de água (Aw) durante a sua maturação. O protocolo de maturação ainda não está determinado na legislação brasileira; portanto o estudo objetivou: (a) identificar as fases de fermentação e dessecação durante a maturação de salame; (b) testar a sobrevivência de S. enterica durante o processamento de salame e (c) comparar os meios de cultura xilose lisina dextrose (XLD) e thin agar layer (TAL) para recuperação de células do referido micro-organismo. Os salames foram elaborados com um coquetel de S. enterica e submetidos à fermentação em 30ºC e secagem a 20ºC com umidade relativa (UR) controlada. Amostragens periódicas para quantificação de S. enterica, análises de Aw e pH foram realizadas durante a maturação e as curvas foram construídas. A fermentação ocorreu nas primeiras 66 horas, quando houve queda do pH do salame; entretanto S. enterica aumentou sua população nas primeiras 21 horas. A etapa de dessecação foi capaz de reduzir aproximadamente 5 log UFC da população bacteriana em 875 horas, alcançando Aw menor que 0,78, mas não foi capaz de eliminar o micro-organismo do alimento. Para enumeração do micro-organismo, o meio sólido TAL foi mais eficiente na recuperação das células submetidas à maturação quando comparado ao ágar XLD comumente utilizado

Perfil de resistência a antimicrobianos de amostras de Salmonella sp. isoladas de cortes de pernil suíno no Rio Grande do Sul

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Perception of poultry veterinarians on the use of antimicrobials and antimicrobial resistance in egg production

This study aimed to describe the perception of veterinarians who work with commercial laying hens in the state of Rio Grande do Sul, Brazil, regarding the use of antibiotics and their possible impacts on animal, human, and environmental health. A descriptive epidemiological study was carried out through face-to-face or web conferencing interviews with the veterinarians that provide technical assistance at commercial laying hen operations. A standardized and structured questionnaire was developed based on the literature and expert opinion, which contained 1 opened and 40 closed questions. Conventional non-probabilistic sampling was used, based on an initial list of 15 veterinarians registered in the Poultry Production Association of Rio Grande do Sul, followed by the snowball technique. The acquisition of 26 contacts of veterinarians was accomplished, and 16 were interviewed. Through the answers obtained it was possible to verify that the interviewees' understanding regarding both the antibiotic resistance impact and the decision-making about the use of antibiotics seem to be linked to their practical experiences. Besides that, according to the veterinarians, farmers can acquire and administer the antimicrobials on their farms. Moreover, both farm storage and administration of lower doses of antibiotics than the recommended one could be contributing factors to resistant bacteria selection. Furthermore, controversially, the professionals believed that resistant bacteria can be transmitted to humans from eggs, but they said that there are no bacteria in eggs. Therefore, the veterinarians practices can be improved considering national and international guidelines on antimicrobial resistance to minimize the development of resistance. Finally, it is expected that the present results will contribute to a more complex discussion about antimicrobial resistance, helping to formulate public policies in the egg production industry

Use of a modified AFLP protocol to discriminate Salmonella enterica subsp.enterica serovar Enteritidis isolates

Salmonella enterica  subsp. enterica (S.) serovar Enteritidis is one of the main pathogens involved in food-borne diseases worldwide. In epidemiological investigations of food-related salmonellosis, subtyping is necessary to improve preventive and control measures. Single-enzyme amplified fragment length polymorphism (SE-AFLP) analysis is a modified AFLP that uses only one restriction enzyme to produce DNA fragments that are selectively amplified by PCR. In order to assess the applicability of SE-AFLP in S. Enteritidis typing, one hundred and eight strains isolated from poultry, swine and also from human salmonellosis outbreaks in Southern Brazil were analyzed. Strains from other countries and six different S. enterica serovars were also included as controls. SE-AFLP was able to distinguish S. Enteritidis from the other S. enterica serovars analyzed. However, most of S. Enteritidis strains isolated from poultry, salmonellosis outbreaks and most of the strains from other countries shared the same predominant pattern. The low genetic diversity identified in S. Enteritidis suggests that the strains analyzed are clonally related and one predominant SE-AFLP genotype is widely spread in Southern Brazil

Qualidade microbiológica de queijos coloniais comercializados em Porto Alegre-RS

Colonial cheese is a traditional dairy product in southern Brazil and is commonly purchased by the citizens of Porto Alegre. However, there is still a lack of technical regulation of colonial cheese, and there is little information about the microbiological quality of this product at the retail level. Thus, the objectives of this study were to (i) evaluate compliance with the legal microbiological standards of colonial cheese sampled from street fairs and the central market of the city of Porto Alegre; (ii) statistically test the hypothesis of an association between noncompliance with the standards and local purchasing (street fairs or central market); (iii) estimate the number of Listeria spp. and Listeria monocytogenes in the positive samples; and (iv) characterize the L. monocytogenes strains by serotyping and macrorestriction (PFGE). For this purpose, 205 cheese samples belonging to 17 different brands were analyzed. The microbiological analyses were conducted according to ISO standardized protocols for the detection of L. monocytogenes and Salmonella spp. or by enumeration of coagulase-positive Staphylococcus and coliforms at 45°C. Among the samples, 47.31% did not comply with at least one of the microbiological standards established by the Brazilian legislation and were thus unsuitable for human consumption. Regarding the coliforms at 45ºC and coagulase-positive Staphylococcus, 10.73% and 40.48% of the samples presented higher counts than the legal parameter, respectively. There was no association between the frequency of samples with coagulase-positive Staphylococcus counts above the legal parameter and local of purchasing; however, the commercial brand influenced the frequency of unsuitable samples This may indicate failures of hygiene during cheese production. Salmonella spp. were not detected. Listeria monocytogenes was isolated from 2.9% of the samples. The estimated average populations of Listeria spp. and L. monocytogenes were low in the positive cheese samples at -3.3 log CFU g‾1 and -2.26 log CFU g‾¹, respectively. The strains of L. monocytogenes belonged to serovars 1/2a, 1/2b and 1/2c and could be grouped into five pulsotypes with no evident epidemiological relation among them. The results demonstrate the need to improve the hygiene procedures during colonial cheese production and to strengthen monitoring at the dairy plants and retail levels.O queijo colonial é um derivado lácteo típico do sul do Brasil, e amplamente adquirido pela população da cidade de Porto Alegre. Porém, esse produto lácteo ainda não conta com regulamento técnico específico e ainda há poucos dados sobre a qualidade microbiológica dos queijos ofertados à população. Sendo assim, os objetivos do estudo foram: (i) avaliar os parâmetros microbiológicos previstos na legislação em queijos coloniais comercializados em Feiras Modelo e Mercado Público de Porto Alegre; (ii) testar hipóteses estatísticas de associação entre violação do padrão microbiológico estabelecido na legislação com o ponto de comercialização; (iii) estimar a distribuição de contagem de Listeria sp. e L. monocytogenes nos queijos em que esta bactéria foi detectada e (iv) caracterizar as cepas de L. monocytogenes por sorotipificação e macro-restrição. Para tanto, foram analisadas 205 amostras de queijo, compreendendo 17 marcas distintas. As análises microbiológicas foram conduzidas conforme protocolos padronizados de análise de alimentos e evidenciaram que 47,31% dos queijos estavam não conformes com pelo menos um dos parâmetros microbiológicos estabelecidos na RDC nº12/2001, portanto impróprios ao consumo humano. Com relação à quantificação de coliformes a 45ºC e Staphylococcus coagulase positiva, respectivamente, 10,73% e 40,48% das amostras apresentaram contagens superiores ao estabelecido na legislação A distribuição das amostras não conformes com o parâmetro Staphylococcus coagulase positiva não esteve associada ao ponto de comercialização, mas foi influenciada pela marca comercial do queijo, indicando possíveis falhas na elaboração dos mesmos. Não houve detecção de Salmonella sp. e em 2,9% das amostras havia presença de L. monocytogenes. A população média estimada nos queijos positivos para Listeria sp. e L. monocytogenes foi baixa, respectivamente, -3,3 log UFC g-1 e -2,26 log UFC g-1. As cepas de L. monocytogenes pertenciam aos sorovares 1/2a, 1/2b e 1/2c e a macro-restrição demonstrou a presença de cinco pulsotipos sem relação epidemiológica evidente. Os resultados demonstram a necessidade de melhorar a qualidade higiênica da elaboração do queijo colonial e aumentar a fiscalização sanitária desse produto