Classification of Avian Pathogenic Escherichia coli (APEC) and Human Uropathogenic Escherichia coli (UPEC) in Phylogenetic Groups and Association with Pathogenicity In Vivo

Background: Avian pathogenic E. coli (APEC) and uropathogenic E. coli (UPEC) are responsible, respectively, for avian colibacillosis and for 80% of urinary tract infections in humans. E. coli control is difficult due to the absence of a reliable method to differentiate pathogenic and commensal strains. Genetic similarity between APEC and UPEC suggests a common ancestral origin and the capability of potentially pathogenic strains to affect human health. The classification in phylogenetic groups facilitates the identification of pathogenic strains. The objective of this work was to classify APEC and UPEC E. coli strains into phylogenetic groups and to associate it with in vivo pathogenicity.Materials, Methods & Results: 460 APEC and 450 UPEC strains, stored in BHI with glycerol at -80C, were selected. APEC strains were isolated from cellulitis, respiratory tract and poultry litter of broiler flocks from Southern Brazil. The UPEC strains from urinary tract infection were provided by a hospital in Porto Alegre. After DNA extraction, APEC and UPEC strains were classified into four phylogenetic groups (A, B1, B2 and D) by a multiplex-PCR protocol for the detection of the chuA and yjaA genes and the TspE4.C2 DNA fragment. Phylogenetic groups were associated with pathogenicity indexes (PI), presented on a scale of 0 to 10, which were previously obtained through the inoculation of

Classification of Avian Pathogenic Escherichia coli (APEC) and Human Uropathogenic Escherichia coli (UPEC) in Phylogenetic Groups and Association with Pathogenicity In Vivo

Background: Avian pathogenic E. coli (APEC) and uropathogenic E. coli (UPEC) are responsible, respectively, for avian colibacillosis and for 80% of urinary tract infections in humans. E. coli control is difficult due to the absence of a reliable method to differentiate pathogenic and commensal strains. Genetic similarity between APEC and UPEC suggests a common ancestral origin and the capability of potentially pathogenic strains to affect human health. The classification in phylogenetic groups facilitates the identification of pathogenic strains. The objective of this work was to classify APEC and UPEC E. coli strains into phylogenetic groups and to associate it with in vivo pathogenicity.Materials, Methods & Results: 460 APEC and 450 UPEC strains, stored in BHI with glycerol at -80C, were selected. APEC strains were isolated from cellulitis, respiratory tract and poultry litter of broiler flocks from Southern Brazil. The UPEC strains from urinary tract infection were provided by a hospital in Porto Alegre. After DNA extraction, APEC and UPEC strains were classified into four phylogenetic groups (A, B1, B2 and D) by a multiplex-PCR protocol for the detection of the chuA and yjaA genes and the TspE4.C2 DNA fragment. Phylogenetic groups were associated with pathogenicity indexes (PI), presented on a scale of 0 to 10, which were previously obtained through the inoculation of

Classification of Avian Pathogenic Escherichia coli (APEC) and Human Uropathogenic Escherichia coli (UPEC) in Phylogenetic Groups and Association with Pathogenicity In Vivo

Background: Avian pathogenic E. coli (APEC) and uropathogenic E. coli (UPEC) are responsible, respectively, for avian colibacillosis and for 80% of urinary tract infections in humans. E. coli control is difficult due to the absence of a reliable method to differentiate pathogenic and commensal strains. Genetic similarity between APEC and UPEC suggests a common ancestral origin and the capability of potentially pathogenic strains to affect human health. The classification in phylogenetic groups facilitates the identification of pathogenic strains. The objective of this work was to classify APEC and UPEC E. coli strains into phylogenetic groups and to associate it with in vivo pathogenicity.Materials, Methods & Results: 460 APEC and 450 UPEC strains, stored in BHI with glycerol at -80C, were selected. APEC strains were isolated from cellulitis, respiratory tract and poultry litter of broiler flocks from Southern Brazil. The UPEC strains from urinary tract infection were provided by a hospital in Porto Alegre. After DNA extraction, APEC and UPEC strains were classified into four phylogenetic groups (A, B1, B2 and D) by a multiplex-PCR protocol for the detection of the chuA and yjaA genes and the TspE4.C2 DNA fragment. Phylogenetic groups were associated with pathogenicity indexes (PI), presented on a scale of 0 to 10, which were previously obtained through the inoculation of

Classification of Avian Pathogenic Escherichia coli (APEC) and Human Uropathogenic Escherichia coli (UPEC) in Phylogenetic Groups and Association with Pathogenicity In Vivo

Background: Avian pathogenic E. coli (APEC) and uropathogenic E. coli (UPEC) are responsible, respectively, for avian colibacillosis and for 80% of urinary tract infections in humans. E. coli control is difficult due to the absence of a reliable method to differentiate pathogenic and commensal strains. Genetic similarity between APEC and UPEC suggests a common ancestral origin and the capability of potentially pathogenic strains to affect human health. The classification in phylogenetic groups facilitates the identification of pathogenic strains. The objective of this work was to classify APEC and UPEC E. coli strains into phylogenetic groups and to associate it with in vivo pathogenicity.Materials, Methods & Results: 460 APEC and 450 UPEC strains, stored in BHI with glycerol at -80C, were selected. APEC strains were isolated from cellulitis, respiratory tract and poultry litter of broiler flocks from Southern Brazil. The UPEC strains from urinary tract infection were provided by a hospital in Porto Alegre. After DNA extraction, APEC and UPEC strains were classified into four phylogenetic groups (A, B1, B2 and D) by a multiplex-PCR protocol for the detection of the chuA and yjaA genes and the TspE4.C2 DNA fragment. Phylogenetic groups were associated with pathogenicity indexes (PI), presented on a scale of 0 to 10, which were previously obtained through the inoculation of

Classification of Avian Pathogenic Escherichia coli (APEC) and Human Uropathogenic Escherichia coli (UPEC) in Phylogenetic Groups and Association with Pathogenicity In Vivo

Background: Avian pathogenic E. coli (APEC) and uropathogenic E. coli (UPEC) are responsible, respectively, for avian colibacillosis and for 80% of urinary tract infections in humans. E. coli control is difficult due to the absence of a reliable method to differentiate pathogenic and commensal strains. Genetic similarity between APEC and UPEC suggests a common ancestral origin and the capability of potentially pathogenic strains to affect human health. The classification in phylogenetic groups facilitates the identification of pathogenic strains. The objective of this work was to classify APEC and UPEC E. coli strains into phylogenetic groups and to associate it with in vivo pathogenicity.Materials, Methods & Results: 460 APEC and 450 UPEC strains, stored in BHI with glycerol at -80C, were selected. APEC strains were isolated from cellulitis, respiratory tract and poultry litter of broiler flocks from Southern Brazil. The UPEC strains from urinary tract infection were provided by a hospital in Porto Alegre. After DNA extraction, APEC and UPEC strains were classified into four phylogenetic groups (A, B1, B2 and D) by a multiplex-PCR protocol for the detection of the chuA and yjaA genes and the TspE4.C2 DNA fragment. Phylogenetic groups were associated with pathogenicity indexes (PI), presented on a scale of 0 to 10, which were previously obtained through the inoculation of

Classification of Avian Pathogenic Escherichia coli (APEC) and Human Uropathogenic Escherichia coli (UPEC) in Phylogenetic Groups and Association with Pathogenicity In Vivo

Background: Avian pathogenic E. coli (APEC) and uropathogenic E. coli (UPEC) are responsible, respectively, for avian colibacillosis and for 80% of urinary tract infections in humans. E. coli control is difficult due to the absence of a reliable method to differentiate pathogenic and commensal strains. Genetic similarity between APEC and UPEC suggests a common ancestral origin and the capability of potentially pathogenic strains to affect human health. The classification in phylogenetic groups facilitates the identification of pathogenic strains. The objective of this work was to classify APEC and UPEC E. coli strains into phylogenetic groups and to associate it with in vivo pathogenicity.Materials, Methods & Results: 460 APEC and 450 UPEC strains, stored in BHI with glycerol at -80C, were selected. APEC strains were isolated from cellulitis, respiratory tract and poultry litter of broiler flocks from Southern Brazil. The UPEC strains from urinary tract infection were provided by a hospital in Porto Alegre. After DNA extraction, APEC and UPEC strains were classified into four phylogenetic groups (A, B1, B2 and D) by a multiplex-PCR protocol for the detection of the chuA and yjaA genes and the TspE4.C2 DNA fragment. Phylogenetic groups were associated with pathogenicity indexes (PI), presented on a scale of 0 to 10, which were previously obtained through the inoculation of

Simulação de condições de uso de quaternário de amônio frente amostras de italic>Salmonella /italic> Hadar isoladas de carcaças de frango

p>Biosafety measures are adopted in order to avoid the spreading of pathogenic microorganisms along the poultry chain, with disinfection being a mandatory procedure and the chemical compound benzalkonium chloride (quaternary ammonium) widely used for this purpose. Due to the fact that part of the farming in Brazil is located in areas with a great thermal amplitude, which is also the case among the different areas and sections of slaughterhouses, we performed an experiment to verify the activity of this disinfectant, simulating conditions of use with 33 italic>Salmonella /italic> Hadar isolates. Using the test suspension, the inactivation of the bacteria was monitored under different concentrations (100 and 200 ppm), temperatures (20 ± 2 ºC and 8 ± 2 ºC), organic matter loading (1 and 3 %) and contact times (5, 10 and 20 minutes). As a result, all isolates in the two concentrations and organic loading were inactivated at 20 ± 2 ºC after a contact time of 5 minutes. At a temperature of 8 ± 2 ºC, the disinfectants activity was affected, with bacterial isolates surviving under all adverse variables (33,3% in front of 100 ppm and 6,1% in front of 200 ppm). Under the conditions of the experiment, our conclusion is that benzalkonium chloride was able to inactivate all isolates of the italic>Salmonella /italic> serovars found and, therefore, it can be used in disinfection procedures. However, a low room temperature is a factor that limits indicating its use. /p>

p>Para impedir a dispersão de microrganismos patogênicos ao longo da cadeia avícola medidas de biosseguridade são adotadas, sendo a desinfecção procedimento obrigatório e o composto químico cloreto de benzalcônio (quaternário de amônio) largamente usado para essa finalidade. Devido ao fato de que parte das criações brasileiras localizam-se em regiões com grande amplitude térmica, o mesmo ocorrendo entre as diferentes áreas e secções de matadouros-frigoríficos, executou-se este experimento para verificar a atividade desse desinfetante simulando condições de uso frente a 33 isolados de italic>Salmonella /italic>Hadar. Pelo teste de suspensão observou-se a inativação bacteriana sob as variáveis concentração (100 e 200 ppm), temperatura (20 ± 2 ºC e 8 ± 2 ºC), carga de matéria orgânica (1 e 3 %) e tempos de contato (5, 10 e 20 minutos). Como resultados, a 20 ± 2 ºC todos os isolados foram inativados nas duas concentrações e cargas orgânicas após 5 minutos de contato. Sob temperatura de 8 ± 2 ºC o desinfetante teve sua atividade comprometida, tendo isolados bacterianos sobrevivido sob todas as variáveis de confronto (33,3% frente 100 ppm e 6,1% frente 200 ppm). Quanto menor a concentração do desinfetante e maior carga orgânica, maior o número de isolados viáveis. Conclui-se que, nas condições do experimento, o cloreto de benzalcônio foi capaz de inativar todos os isolados do sorovar de italic>Salmonella /italic> confrontados, podendo ser empregado nos procedimentos de desinfecção. No entanto, a baixa temperatura ambiente é fator de limitação na indicação de seu uso. /p>

Simulação de condições de uso de quaternário de amônio frente amostras de italic>Salmonella /italic> Hadar isoladas de carcaças de frango

p>Biosafety measures are adopted in order to avoid the spreading of pathogenic microorganisms along the poultry chain, with disinfection being a mandatory procedure and the chemical compound benzalkonium chloride (quaternary ammonium) widely used for this purpose. Due to the fact that part of the farming in Brazil is located in areas with a great thermal amplitude, which is also the case among the different areas and sections of slaughterhouses, we performed an experiment to verify the activity of this disinfectant, simulating conditions of use with 33 italic>Salmonella /italic> Hadar isolates. Using the test suspension, the inactivation of the bacteria was monitored under different concentrations (100 and 200 ppm), temperatures (20 ± 2 ºC and 8 ± 2 ºC), organic matter loading (1 and 3 %) and contact times (5, 10 and 20 minutes). As a result, all isolates in the two concentrations and organic loading were inactivated at 20 ± 2 ºC after a contact time of 5 minutes. At a temperature of 8 ± 2 ºC, the disinfectants activity was affected, with bacterial isolates surviving under all adverse variables (33,3% in front of 100 ppm and 6,1% in front of 200 ppm). Under the conditions of the experiment, our conclusion is that benzalkonium chloride was able to inactivate all isolates of the italic>Salmonella /italic> serovars found and, therefore, it can be used in disinfection procedures. However, a low room temperature is a factor that limits indicating its use. /p>

p>Para impedir a dispersão de microrganismos patogênicos ao longo da cadeia avícola medidas de biosseguridade são adotadas, sendo a desinfecção procedimento obrigatório e o composto químico cloreto de benzalcônio (quaternário de amônio) largamente usado para essa finalidade. Devido ao fato de que parte das criações brasileiras localizam-se em regiões com grande amplitude térmica, o mesmo ocorrendo entre as diferentes áreas e secções de matadouros-frigoríficos, executou-se este experimento para verificar a atividade desse desinfetante simulando condições de uso frente a 33 isolados de italic>Salmonella /italic>Hadar. Pelo teste de suspensão observou-se a inativação bacteriana sob as variáveis concentração (100 e 200 ppm), temperatura (20 ± 2 ºC e 8 ± 2 ºC), carga de matéria orgânica (1 e 3 %) e tempos de contato (5, 10 e 20 minutos). Como resultados, a 20 ± 2 ºC todos os isolados foram inativados nas duas concentrações e cargas orgânicas após 5 minutos de contato. Sob temperatura de 8 ± 2 ºC o desinfetante teve sua atividade comprometida, tendo isolados bacterianos sobrevivido sob todas as variáveis de confronto (33,3% frente 100 ppm e 6,1% frente 200 ppm). Quanto menor a concentração do desinfetante e maior carga orgânica, maior o número de isolados viáveis. Conclui-se que, nas condições do experimento, o cloreto de benzalcônio foi capaz de inativar todos os isolados do sorovar de italic>Salmonella /italic> confrontados, podendo ser empregado nos procedimentos de desinfecção. No entanto, a baixa temperatura ambiente é fator de limitação na indicação de seu uso. /p>

Utilização de inteligência artificial (redes neurais artificiais) para a classificação do comportamento bioquímico de amostras de Escherichia coli isoladas de frangos de corte

A  Escherichia coli é comumente encontrada na avicultura e muitas vezes sua presença no organismo dos animais e/ou contaminando as camas de aviários não causa estranheza. Por outro lado, a utilização de inteligência artificial, especificamente redes neurais artificiais, está sendo crescentemente empregada como ferramenta para medir relações não lineares entre variáveis. Neste trabalho foram usados os dados disponíveis referentes a 261 amostras da bactéria oriundas de camas de aviários, lesões de celulite e quadros respiratórios de frangos de corte. O diagnóstico laboratorial envolveu o isolamento do agente, a caracterização dos genes associados à virulência, as lesões provocadas pela inoculação em pintos, o Índice de Patogenicidade das amostras e a resistência antimicrobiana a 14 antibióticos que foram as entradas das redes neurais e sete provas bioquímicas as saídas. A principal conclusão deste artigo foi de que as redes neurais foram capazes de realizar a classificação correta do comportamento das amostras com amplitude de 87,80% a 98,37%. A sensibilidade e a especificidade das classificações obtidas variaram de 59,32% a 99,47% e de 80,00% a 98,54%, respectivamente.

Utilização de inteligência artificial (redes neurais artificiais) para a classificação do comportamento bioquímico de amostras de Escherichia coli isoladas de frangos de corte

A  Escherichia coli é comumente encontrada na avicultura e muitas vezes sua presença no organismo dos animais e/ou contaminando as camas de aviários não causa estranheza. Por outro lado, a utilização de inteligência artificial, especificamente redes neurais artificiais, está sendo crescentemente empregada como ferramenta para medir relações não lineares entre variáveis. Neste trabalho foram usados os dados disponíveis referentes a 261 amostras da bactéria oriundas de camas de aviários, lesões de celulite e quadros respiratórios de frangos de corte. O diagnóstico laboratorial envolveu o isolamento do agente, a caracterização dos genes associados à virulência, as lesões provocadas pela inoculação em pintos, o Índice de Patogenicidade das amostras e a resistência antimicrobiana a 14 antibióticos que foram as entradas das redes neurais e sete provas bioquímicas as saídas. A principal conclusão deste artigo foi de que as redes neurais foram capazes de realizar a classificação correta do comportamento das amostras com amplitude de 87,80% a 98,37%. A sensibilidade e a especificidade das classificações obtidas variaram de 59,32% a 99,47% e de 80,00% a 98,54%, respectivamente.

Antibiotic resistance in Salmonella Enteritidis isolated from broiler carcasses

Eighty Salmonella Enteritidis strains isolated from broiler carcasses between May 1995 and April 1996 in the State of Rio Grande do Sul, Brazil, were tested for antibiotic susceptibility using the disk diffusion method. Resistance to colistin, novobiocin, erythromycin and tetracycline was observed in 100% of the isolates. The strains showed intermediate resistance at different levels to kanamycin (1.25%), enrofloxacin (3.75%), neomycin (3.75%), fosfomycin (20%), sulphonamides (86.25%) and nitrofurantoin (90%). Resistance to ciprofloxacin, norfloxacin, gentamicin, polymyxin B, sulphametrim and sulphazotrim was not found. Since resistance to antibiotics especially those introduced in the last decades, was detected, it is recommended that their use must be based on the results of resistance tests or minimum inhibitory concentration tests.

Oitenta amostras de Salmonella Enteritidis isoladas de carcaças de frango no período entre maio de 1995 a abril de 1996 no Estado do Rio Grande do Sul, Brasil foram testados para susceptibilidade antimicrobiana pelo método de antibiograma. O antibiograma das amostras apresentou 100% de resistência a colistina, novobiocina, eritromicina e tetraciclina. Tiveram resistência em diferentes níveis a canamicina (1,25%), enrofloxacina (3,75%), neomicina (3,75%), fosfomicina (20%), sulfonamida (86,25%) e nitrofurantoína (90%) e por outro lado não apresentaram resistência a ciprofloxacina, norfloxacina, gentamicina, polimixina B, sulfametrim e sulfazotrim. A constatação de resistência a antibióticos, inclusive àqueles introduzidos na última década, enfatiza a necessidade de uso responsável de antibióticos, e com base em antibiograma ou concentração inibitória mínima.

Detecção de Ornithobacterium rhinotracheale (ORT) por meio da reação em cadeia da polimerase (PCR)

Ornithobacterium rhinotracheale (ORT) is a recently discovered Gram negative bacterium that has been associated with respiratory diseases in commercial poultry and wild birds from many countries. In Brazil, antibodies were detected in some broiler and breeder flocks from the States of São Paulo and Minas Gerais. Because the bacteria is difficult to grow, the Polymerase Chain Reaction (PCR) has been found to be suitable for identification and diagnostic purposes. The aim of the present work was to verify the occurrence of ORT in Rio Grande do Sul through the detection of the bacteria DNA. Tracheal swabs (84) were collected from 14 broiler flocks of distinct companies. DNA was purified and PCR performed with species specific primers from the ORT 16S ribosomal RNA gene. Amplification products with 784 base pairs were obtained from 10 out of the 84 samples. The positive samples were from four flocks of tree companies established in different regions of the state. The results indicate that this respiratory pathogen occurs in major broiler producing areas from the State of Rio Grande do Sul. Further studies are under way to determine the prevalence of this pathogen and to characterize the strains isolated.

Ornithobacterium rhinotracheale (ORT) é uma bactéria Gram negativa recentemente descrita que se encontra associada às doenças do trato respiratório em criações de aves comerciais e silvestres em vários países do mundo. No Brasil, foram detectados anticorpos em um pequeno número de frangos de corte e suas matrizes dos Estados de São Paulo e Minas Gerais. Como a bactéria é fastidiosa, a Reação em Cadeia da Polimerase (PCR) torna-se útil para sua detecção e identificação. O presente trabalho visou verificar a ocorrência da ORT no Rio Grande do Sul pela detecção do DNA da bactéria. Foram coletadas 84 amostras de suabe de traquéia de aves pertencentes a 14 lotes de diferentes empresas avícolas. O DNA foi purificado e a PCR realizada com iniciadores específicos para o gene do RNA ribossomal 16S da ORT. Foram observados produtos de amplificação com 784 pares de bases em 10 das 84 amostras. As amostras positivas pertenciam a quatro lotes de três empresas estabelecidas em diferentes regiões do RS. Os resultados indicam que este patógeno respiratório de aves existe no Brasil e está presente em importantes regiões criatórias do RS. Outros estudos estão em andamento para determinar a prevalência e caracterização dos isolados obtidos.

Detecção de Ornithobacterium rhinotracheale (ORT) por meio da reação em cadeia da polimerase (PCR)

Ornithobacterium rhinotracheale (ORT) is a recently discovered Gram negative bacterium that has been associated with respiratory diseases in commercial poultry and wild birds from many countries. In Brazil, antibodies were detected in some broiler and breeder flocks from the States of São Paulo and Minas Gerais. Because the bacteria is difficult to grow, the Polymerase Chain Reaction (PCR) has been found to be suitable for identification and diagnostic purposes. The aim of the present work was to verify the occurrence of ORT in Rio Grande do Sul through the detection of the bacteria DNA. Tracheal swabs (84) were collected from 14 broiler flocks of distinct companies. DNA was purified and PCR performed with species specific primers from the ORT 16S ribosomal RNA gene. Amplification products with 784 base pairs were obtained from 10 out of the 84 samples. The positive samples were from four flocks of tree companies established in different regions of the state. The results indicate that this respiratory pathogen occurs in major broiler producing areas from the State of Rio Grande do Sul. Further studies are under way to determine the prevalence of this pathogen and to characterize the strains isolated.

Ornithobacterium rhinotracheale (ORT) é uma bactéria Gram negativa recentemente descrita que se encontra associada às doenças do trato respiratório em criações de aves comerciais e silvestres em vários países do mundo. No Brasil, foram detectados anticorpos em um pequeno número de frangos de corte e suas matrizes dos Estados de São Paulo e Minas Gerais. Como a bactéria é fastidiosa, a Reação em Cadeia da Polimerase (PCR) torna-se útil para sua detecção e identificação. O presente trabalho visou verificar a ocorrência da ORT no Rio Grande do Sul pela detecção do DNA da bactéria. Foram coletadas 84 amostras de suabe de traquéia de aves pertencentes a 14 lotes de diferentes empresas avícolas. O DNA foi purificado e a PCR realizada com iniciadores específicos para o gene do RNA ribossomal 16S da ORT. Foram observados produtos de amplificação com 784 pares de bases em 10 das 84 amostras. As amostras positivas pertenciam a quatro lotes de três empresas estabelecidas em diferentes regiões do RS. Os resultados indicam que este patógeno respiratório de aves existe no Brasil e está presente em importantes regiões criatórias do RS. Outros estudos estão em andamento para determinar a prevalência e caracterização dos isolados obtidos.

Utilization of immunomagnetic separation for detection of Salmonella in raw broiler parts

This study was conducted aiming to compare the conventional microbiological method to detect Salmonella in broiler parts with the Immunomagnetic Separation method (IMS) followed by plate isolation and also the IMS associated with Rappaport-Vassiliadis broth (RV). The IMS was performed following a pre- enrichment step in buffered peptone water. Sixty-one samples (raw broiler parts) were tested and the results showed that the use of the IMS method alone allowed the isolation of Salmonella in 9 of the tested samples, while the association IMS/RV detected the agent in 30 samples. The conventional microbiological method was able to isolate the agent in 25 opportunities. These results allowed to conclude that the IMS/RV association presented an increased sensitivity and permitted a better isolation of Salmonella. The conclusion was that other means of isolation, in particular those which do not interfere with the growth of bead bounded Salmonella, should be searched.

Este trabalho foi conduzido com o objetivo de comparar o método microbiológico convencional para detecção de Salmonella em partes de frango, com o método de separação imunomagnética (IMS) e de separação imunomagnética associada ao caldo Rappaport-Vassiliadis (RV). A IMS foi realizada a partir do caldo de pré-enriquecimento. Os resultados obtidos nas 61 amostras (partes de frango) testadas indicam que a separação imunomagnética seguida de plaqueamento em meio sólido isolou o agente em 9 das 61 amostras, enquanto a associação IMS/RV isolou o agente em 30 das 61 amostras e o método microbiológico convencional foi capaz de isolar a bactéria em 25 amostras. Através destes resultados, conclui-se que a combinação IMS/RV aumenta a sensibilidade do processo. Outra conclusão possível foi de que deve-se buscar outros meios de isolamento e seleção de colônias (em ágar) que não interfiram no crescimento das salmonelas ligadas aos "beads".