Relação da idade na presença de bactérias resistentes a antimicrobianos em rebanhos leiteiros no Rio Grande do Sul / Age related to the presence of antimicrobial resistant bacteria in twenty one dairy herds in Rio Grande do Sul, Brazil

[...] As bactérias foram isoladas de amostras de leite compostas de todos os quartos mamários de cada vaca após descartar os primeiros três ou quatro jatos de leite. Para acessar os potenciais fatores de risco, características dos animais foram obtidas através de uma entrevista com os produtores. Os exames laboratoriais foram realizados de acordo com as recomendações do National Mastitis Council. Um total de 242 isolados foi obtido de 195 vacas a partir da amostra do rebanho total (251 vacas). A prevalência de infecções foi descrita em grupos de acordo com o perfil epidemiológico: bactérias ambientais, contagiosas e outras. Estas perfizeram 57,3 por cento, 26,3 por cento e 11,2 por cento, respectivamente, dos animais amostrados. Testes de suscetibilidade antimicrobiana contra 12 diferentes antimicrobianos foram realizados em 159 isolados. No total, 30 por cento dos isolados testados mostraram resistência a pelo menos três grupos diferentes de antimicrobianos e foram classificados como multirresistentes. Foram observadas as freqüências mais elevadas de resistência contra a ampicilina para os estafilococos coagulase-negativo, seguida de eritromicina para estafilococos coagulase-positivo e tetraciclina para estreptococos. A análise de regressão logística mostrou uma relação significativa entre a idade das vacas e a presença de estafilococos coagulase-positivo multirresistentes e distribuição de classes diferentes de bactérias nos diferentes estratos etários, o que sugere uma concorrência dinâmica ao longo do tempo (p < 0,05). Animais com três a quatro anos tiveram 13,7 vezes mais chances (IC95 por cento 1,4 - 130,2, p = 0,02) de ter estafilococos coagulase-positivo multirresistentes em comparação com aqueles com dois ou três anos. O tempo de exposição a agentes infecciosos e consequentes terapias sugere uma maior chance de colonização do úbere por patógenos resistentes devido à pressão de seleção repetida durante a vida.(AU)

[...] Bacteria were isolated from composite milk samples obtained from all quarters of each cow after discarding the initial three or four streams of milk. To access potential risk factors, animal characteristics were obtained through an interview with the producers. Laboratory tests were done according to National Mastitis Council recommendations. A total of 242 isolates was obtained from 195 cows out of 251 cows sampled. The prevalence of animal infections was described in groups according to the epidemiological profile: environmental, contagious and other bacteria. These were 57.3 percent, 26.3 percent and 11.2 percent, respectively of the sampled animals. Antimicrobial susceptibility tests against 12 different antimicrobials were performed in 159 isolates. Altogether, 30 percent of the isolates tested showed resistance to at least three different antimicrobial groups and were classified as multidrug-resistant. Higher frequencies of resistance were observed against ampicillin to coagulase-negative staphylococci, followed by erythromycin to coagulase-positive staphylococci and tetracycline to streptococci. The logistic regression analysis showed a significant relationship between age of the cows and presence of multidrug-resistant coagulase-positive staphylococci and distribution of different class of bacteria, suggesting a competition dynamic throughout the ages (p < 0.05). Animals with three to four years old had 13.7 times more chances (IC95 percent 1.4 - 130.2; p = 0,02) to have multidrug-resistant coagulase-positive staphylococci compared to those with two to three years. Time of exposure to infectious agents and consequent therapies suggests a greater chance of udder's colonization by resistant pathogens due to repeatedly selection pressure during lifetime.(AU)

Perfil de resistência a antimicrobianos e avaliação da presença de grupos clonais em isolados de Salmonella Bredeney de linfonodos submandibulares de suínos e matéria-prima para fabricação de embutidos / Antimicrobial resistance profile and assessment of clonal groups in Salmonella Bredeney isolated from pig submandibular lymph nodes and minced meat for sausage production

Background: Salmonella is an important agent of the foodborne disease and can be vehiculated by products of animal origin. In recent years, the risk that pathogenic bacteria resistant to antimicrobial enter the food production chain and be transmitted to consumer is a growing concern. Salmonella Bredeney is one of the most prevalent serovar isolated from lymph nodes of slaughter pigs, and the contamination of pork with this serovar has been reported. Therefore, the purpose of this study was to determine the resistance profile and clonality of Salmonella Bredeney isolates from submandibular lymph nodes and minced meat originated from common slaughter pig batches. Materials, Methods & Results: Fifty three isolates of Salmonella enterica serovar Bredeney from submandibular lymph nodes (n = 14) and minced meat used for fresh sausage production (n = 39) originated from five slaughter batch were evaluated. Antimicrobial resistance was determined by the agar disk diffusion tests using disks with the following antimicrobials: nalidixic acid (Na, 30 µg), ciprofloxacin (Cip, 5 µg), gentamicin (Cn, 10 µg), sulphonamide (S3, 300 µg) and tetracycline (Te, 30µg). Later on, isolates that presented the most common resistance profile were submitted to Xba I macrorestrition and analyzed by pulsed-field gel electrophoresis (PFGE). Among the S. Bredeney isolates, 40 (75.5%) were resistant to at least one of the tested antimicrobials. Resistance against tetracycline was the most frequent (32 isolates, 61.5%), followed by resistance to sulphonamide (n = 21, 39.6%), gentamicin (n = 5, 9.4%) and nalidixic acid (n = 3, 5.6%). All strains were susceptible to ciprofloxacin. The profile resistance to tetracycline-sulphonamide (TeS3) was detected in 16 isolates from minced meat and two isolated from lymph nodes. PFGE analysis of these isolates showed six different pulsotypes. The pulsotypeA1 was the most frequent among the isolates, and pulsotype A2 was present in isolates from submandibular lymph nodes and minced meat originated from a common slaughter batch. Discussion: The analyzed isolated of Salmonella Bredeney showed lower multiresistance frequency when compared with previous reports. Resistance to tetracycline and sulphonamide were the most prevalent in line with other studies conducted with porcine Salmonella isolates. Overall, the resistance pattern TeS3 was the most common among the isolates, and was present in 16 isolates from minced meat and in two isolates from submandibular lymph nodes. This pattern is possibly related to the frequent prophylactic and therapeutic use of these antimicrobials in pigs. Strains presenting the resistance pattern TeS3 showed a high diversity of XbaI-pulsotypes. Nonetheless, it was possible to identify a common pulsotype between strains from lymph nodes and minced meat. Fresh pork sausage is not submitted to a thermal treatment step in its manufacturing process. Moreover, the survival of Salmonella strains at the refrigeration temperatures used during the shelf life of fresh pork sausages has been reported. In spite of the fact that pork sausages are mainly consumed after cooking, the hazard of cross-contamination during preparation and the insufficient thermal treatment leading to Salmonella-transmission to consumers, still remains. It leads to the conclusion that resistant Salmonella strains originated from slaughter pig can be present in pork products consumed by the population.(AU)

Perfil de resistência a antimicrobianos e avaliação da presença de grupos clonais em isolados de Salmonella Bredeney de linfonodos submandibulares de suínos e matéria-prima para fabricação de embutidos / Antimicrobial resistance profile and assessment of clonal groups in Salmonella Bredeney isolated from pig submandibular lymph nodes and minced meat for sausage production

Background: Salmonella is an important agent of the foodborne disease and can be vehiculated by products of animal origin. In recent years, the risk that pathogenic bacteria resistant to antimicrobial enter the food production chain and be transmitted to consumer is a growing concern. Salmonella Bredeney is one of the most prevalent serovar isolated from lymph nodes of slaughter pigs, and the contamination of pork with this serovar has been reported. Therefore, the purpose of this study was to determine the resistance profile and clonality of Salmonella Bredeney isolates from submandibular lymph nodes and minced meat originated from common slaughter pig batches. Materials, Methods & Results: Fifty three isolates of Salmonella enterica serovar Bredeney from submandibular lymph nodes (n = 14) and minced meat used for fresh sausage production (n = 39) originated from five slaughter batch were evaluated. Antimicrobial resistance was determined by the agar disk diffusion tests using disks with the following antimicrobials: nalidixic acid (Na, 30 µg), ciprofloxacin (Cip, 5 µg), gentamicin (Cn, 10 µg), sulphonamide (S3, 300 µg) and tetracycline (Te, 30µg). Later on, isolates that presented the most common resistance profile were submitted to Xba I macrorestrition and analyzed by pulsed-field gel electrophoresis (PFGE). Among the S. Bredeney isolates, 40 (75.5%) were resistant to at least one of the tested antimicrobials. Resistance against tetracycline was the most frequent (32 isolates, 61.5%), followed by resistance to sulphonamide (n = 21, 39.6%), gentamicin (n = 5, 9.4%) and nalidixic acid (n = 3, 5.6%). All strains were susceptible to ciprofloxacin. The profile resistance to tetracycline-sulphonamide (TeS3) was detected in 16 isolates from minced meat and two isolated from lymph nodes. PFGE analysis of these isolates showed six different pulsotypes. The pulsotypeA1 was the most frequent among the isolates, and pulsotype A2 was present in isolates from submandibular lymph nodes and minced meat originated from a common slaughter batch. Discussion: The analyzed isolated of Salmonella Bredeney showed lower multiresistance frequency when compared with previous reports. Resistance to tetracycline and sulphonamide were the most prevalent in line with other studies conducted with porcine Salmonella isolates. Overall, the resistance pattern TeS3 was the most common among the isolates, and was present in 16 isolates from minced meat and in two isolates from submandibular lymph nodes. This pattern is possibly related to the frequent prophylactic and therapeutic use of these antimicrobials in pigs. Strains presenting the resistance pattern TeS3 showed a high diversity of XbaI-pulsotypes. Nonetheless, it was possible to identify a common pulsotype between strains from lymph nodes and minced meat. Fresh pork sausage is not submitted to a thermal treatment step in its manufacturing process. Moreover, the survival of Salmonella strains at the refrigeration temperatures used during the shelf life of fresh pork sausages has been reported. In spite of the fact that pork sausages are mainly consumed after cooking, the hazard of cross-contamination during preparation and the insufficient thermal treatment leading to Salmonella-transmission to consumers, still remains. It leads to the conclusion that resistant Salmonella strains originated from slaughter pig can be present in pork products consumed by the population.

Avaliação da qualidade microbiológica de sashimis à base de salmão, preparados em restaurantes especializados em culinária japonesa / Microbiological quality of salmon-based sashimi prepared at restaurants specialized in japanese food

O estudo avaliou a qualidade microbiológica de amostras de sashimi à base de salmão e as condições higiênico-sanitárias dos restaurantes especializados em culinária japonesa na cidade de Porto Alegre/Brasil, licenciados pelo órgão específico municipal. Cento e oito amostras coletadas de seis restaurantes foram analisadas seguindo-se os parâmetros microbiológicos estipulados pela RDC 12/01 da ANVISA. Das amostras coletadas de quatro (66,6) estabelecimentos (B, C, D e F) foram detectados coliformes termotolerantes acima do limite estabelecido pela legislação, respectivamente, em 11,11, 33,33, 61,11 e 44,44 do total de amostras. Staphylococcus coagulase positiva, Vibrio parahaemolyticus e Salmonella sp. não foram isolados. Conforme a avaliação global dos itens do check-list, não houve restaurantes com condições higiênico-sanitárias inadequadas, sendo três (A, D, E) considerados adequados e os demais aprovados com restrições. Foram encontradas inconformidades quanto à higiene, manipulação e temperatura de armazenamento. Houve associação positiva entre a temperatura aferida no pescado e o percentual de contaminação por coliformes termotolerantes (rs = 0,928; p = 0,008). Das amostras analisadas, 75 foram consideradas em condições sanitárias satisfatórias, mas há necessidade de efetiva aplicação das Boas Práticas de Fabricação, com ênfase nos itens de higiene de superfícies e temperatura de armazenamento.(AU)