Ribotyping and virulence markers has been used to investigate 68 Yersinia pseudotuberculosis strains of serogroups O:1a and O:3. The strains were isolated from clinical material obtained from healthy and sick animals in the Southern region of Brazil. Ribotypes were identified by double digestion of extracted DNA with the restriction endonucleases SmaI and PstI, separation by electrophoresis and hybridization with a digoxigenin-labeled cDNA probe. The presence of the chromosomal virulence marker genes inv, irp1, irp2, psn, ybtE, ybtP-ybtQ, and ybtX-ybtS, of the IS100 insertion sequence, and of the plasmid gene lcrF was detected by polymerase chain reaction. The strains were grouped into four distinct ribotypes, all of them comprising several strains. Ribotypes 1 and 4 presented distinct profiles, with 57.3% genetic similarity, ribotypes 2 and 3 presented 52.5% genetic similarity, and genetic similarity was 45% between these two groups (1/4 and 2/3). All strains possessed the inv, irp1, and irp2 genes. Additionally, strains of serogroup O:1a carried psn, ybtE, ybtP-ybtQ, ybtX-ybtS, and IS100. As expected lcrF was only detected in strains harboring the virulence plasmid. These data demonstrate the presence of Y. pseudotuberculosis strains harboring genotypic virulence markers in the livestock from Southern Brazil and that the dissemination of these bacteria may occur between herds.

The course of in vivo infection of five isolates of Yersinia pseudotuberculosis was followed for three weeks in Swiss mice. The strains were isolated from diarrheic and normal feces and mesenteric lymph nodes of healthy and sick stock animals. Four strains of serogroup O:3 and one of serogroup O:1a, with and without the virulence plasmid, were inoculated intragastrically and intravenously in the mice. Groups of five animals were sacrificed at 6 h and 3, 6, 10, 15, and 21 days after inoculation, and organs and tissues were checked for possible macroscopic alterations. Development of infection was monitored at these times by performing viable bacterial counts in homogenates of selected tissues. The animals were cheked daily for clinical alterations. The results of the study showed that strains with the virulence plasmid infected organs and tissues at various times and at varying intensity by both routes of infection, the strain of type O:1a being the most invasive. Moreover, clinical and pathological alterations occurred only in animals inoculated with bacteria carrying the virulence plasmid, regardless of the route of infection.

Poultry meat and its derivatives are among the foodstuffs considered by environmental health authorities to present the highest risks to the public. A total of 185 samples were collected in five monthly batches, from different processing stages in a sausage plant that uses mechanically-deboned chicken meat (MDCM), and testedfor the presence of Salmonella. Enrichment was carried out in both Kauffman's tetrathionate broth and Rappaport-Vassiliadis broth and isolation on Salmonella-Shigella agar and brilliant-green agar. Live Salmonella bacteria were isolated from six samples of the raw meat and from the emulsion, in batches three, four, and five, but not from any sample in batches one or two. The six isolated strains were all classified as Salmonella Albany, which has not previously been reported in MDCM. Of the two enrichment broths, Rappaport-Vassiliadis gave the better results. The pattern of contamination suggests a probable common source, given that a new supplier was used in the third, fourth, and fifth months. It was also shown that the industrial cooking was effective in preventing Salmonella surviving in the final product.

O monitoramento da qualidade higiênico-sanitária do processamento do "leite" de soja, na UNISOJA, foi realizado através da pesquisa de E. coli e/ou a determinação do NMP de coliformes totais, coliformes fecais (45ºC) e E. coli em dez amostragens consecutivas (236 amostras), coletadas e analisadas em diferentes etapas do processamento. O isolamento de E. coli foi realizado em Ágar EMB, seguido de confirmação bioquímica. Na determinação do NMP foi utilizada a técnica dos tubos múltiplos, que foi calculado utilizando-se a tabela de Hoskins, exceto para o lavado das mãos, cujos resultados foram em termos de presença/ausência. E. coli não foi isolada, quer através da semeadura direta ou a partir dos tubos positivos de Caldo EC. Coliformes totais e/ou coliformes fecais (45ºC) estavam presentes em 42% do total das amostras examinadas, mas a contaminação do produto final, quanto a coliformes fecais, encontrava-se abaixo da determinada pela legislação brasileira (RDC Nº 12, de 02 de janeiro de 2001), portanto dentro dos padrões microbiológicos vigentes no país.

A control of the sanitary-hygienic conditions during the soymilk production was performed at UNISOJA, through the isolation of E. coli and/or the determination of the MPN of total coliform, fecal coliform (45º) and E. coli . In ten occasions, 236 samples were collected and analyzed at different processing stages. The isolation of E. coli was performed using EMB Agar with biochemical confirmation. For the MPN it was used the multiple tube test . The MPN were calculated using the Hoskins table. The results for the samples of washing water hands were given in terms of presence/absence. E. coli was not isolated and its NMP was not determined in any of the analysis realized. Total coliform and/or fecal coliform (45ºC) were present in 42% of the examined samples, but the contamination of the final product, regarding to fecal coliform was inferior to that established by the Brazilian Legislation (RDC. Nº 12, 01/02/2001), therefore in accordance with the microbiological patterns for soymilk in vigor in Brazil .

Lotes de camundongos suiços convencionais foram inoculados tanto por via intragástrica (IG) quanto por via intravenosa (IV) com Yersinia enterocolitica dos sorotipos 0:3, 0:8 e 0:9 e com amostras de yersinias atípicas. Foi mantido um lote de animais não inoculados como controle. Verificou-se qual o período de permanência dessas bactérias no intestino dos animais inoculados. Yersinia enterocolitica dos sorotipos 0:3, 0:8 e 0:9, considerados adaptados ao homem, permaneceram no intestino dos animais inoculados por um período muito maior do que as amostras de Yersinia não adaptadas, quer inoculadas por via intragástrica, quer por via intravenosa.

Conventional swiss mice were innoculated intragastrically (IG) and intravenously (IV) with Yersinia enterocolitica serotypes 0:3, 0:8 and 0:9 and with Yersinia enterocolitica like strains. A control animal group was not innoculated. The period that strains remained in the cecal content after the IG and IV challenge was determined. After IG and IV innoculation, Yersinia enterocolitica serotypes 0:3, 0:8 and 0:9, considered adapted to man, were isolated from the cecal content for a longer period than those considered nonadapted.

Lotes de camundongos suiços convencionais foram inoculados tanto por via intragástrica (IG) quanto por via intravenosa (IV) com Yersinia enterocolitica dos sorotipos 0:3, 0:8 e 0:9 e com amostras de yersinias atípicas. Foi mantido um lote de animais não inoculados como controle. Verificou-se qual o período de permanência dessas bactérias no intestino dos animais inoculados. Yersinia enterocolitica dos sorotipos 0:3, 0:8 e 0:9, considerados adaptados ao homem, permaneceram no intestino dos animais inoculados por um período muito maior do que as amostras de Yersinia não adaptadas, quer inoculadas por via intragástrica, quer por via intravenosa.

Conventional swiss mice were innoculated intragastrically (IG) and intravenously (IV) with Yersinia enterocolitica serotypes 0:3, 0:8 and 0:9 and with Yersinia enterocolitica like strains. A control animal group was not innoculated. The period that strains remained in the cecal content after the IG and IV challenge was determined. After IG and IV innoculation, Yersinia enterocolitica serotypes 0:3, 0:8 and 0:9, considered adapted to man, were isolated from the cecal content for a longer period than those considered nonadapted.

Realizou-se exame microbiológico em 24 amostras de sorvetes não pasteurizados, todos preparados de maneira não industrial e à base de leite (creme, nata, chocolate), fabricados por 12 sorveterias diferentes da cidade de Araraquara, SP. Colheram-se duas amostras de cada sorveteria com intervalo de 15 dias entre as colheitas. Realizaram-se as seguintes provas: contagem de bactérias aeróbicas ou facultativas mesófilas e psicrófilas e de Staphylococcus aureus; determinação do Número Mais Provável (NMP) de coliformes totais e fecais e da presença de Salmonella. As técnicas utilizadas foram aquelas convencionalmente usadas para tais determinações. Não foi encontrada Salmonella em nenhuma das amostras e de cerca de 16,6% delas isolou-se Staphylococcus aureus. Em proporções variáveis verificou-se a presença de microrgarnismos deteriorantes e daqueles indicadores de poluição de origem fecal.

A microbiological examination was made on 24 samples of non pasteurized, non industrial ice cream, all made with milk collected from 12 different ice cream shops in Araraquara, SP, Brazil. For the study, two samples were collected 15 days apart, from each store. The following" tests were made using ice-cream samples: presence or absence of Salmonella; counts of mesophilic and psichrophilic bacteria and Staphylococcus aureus and verification of the Most Probable Number (MPN) of enteric organisms (faecal coliforms and other coliforms). The techniques used were the conventional ones used in such calculations. All samples were negative for Salmonella while about 16.6% showed the presence of Staphylococcus aureus. There were deteriorative microorganisms and faecal coliforms present in varying proportions.

Realizou-se exame microbiológico em 24 amostras de sorvetes não pasteurizados, todos preparados de maneira não industrial e à base de leite (creme, nata, chocolate), fabricados por 12 sorveterias diferentes da cidade de Araraquara, SP. Colheram-se duas amostras de cada sorveteria com intervalo de 15 dias entre as colheitas. Realizaram-se as seguintes provas: contagem de bactérias aeróbicas ou facultativas mesófilas e psicrófilas e de Staphylococcus aureus; determinação do Número Mais Provável (NMP) de coliformes totais e fecais e da presença de Salmonella. As técnicas utilizadas foram aquelas convencionalmente usadas para tais determinações. Não foi encontrada Salmonella em nenhuma das amostras e de cerca de 16,6% delas isolou-se Staphylococcus aureus. Em proporções variáveis verificou-se a presença de microrgarnismos deteriorantes e daqueles indicadores de poluição de origem fecal.

A microbiological examination was made on 24 samples of non pasteurized, non industrial ice cream, all made with milk collected from 12 different ice cream shops in Araraquara, SP, Brazil. For the study, two samples were collected 15 days apart, from each store. The following" tests were made using ice-cream samples: presence or absence of Salmonella; counts of mesophilic and psichrophilic bacteria and Staphylococcus aureus and verification of the Most Probable Number (MPN) of enteric organisms (faecal coliforms and other coliforms). The techniques used were the conventional ones used in such calculations. All samples were negative for Salmonella while about 16.6% showed the presence of Staphylococcus aureus. There were deteriorative microorganisms and faecal coliforms present in varying proportions.

Ao pesquisar-se a presença de Salmonella a partir de materiais diversos, foram empregados vários meios de cultura e entre eles o meio Agar Xilose Lisina Verde Brilhante, com a finalidade de avaliá-lo em relação a outros meios seletivo-indicadores mais comumente empregados no isolamento desses microrganismos. Os resultados mostraram que o meio Agar Xilose Lisina Verde Brilhante foi inferior aos Agar SS e Agar Verde Brilhante, ligeiramente superior ao Agar EMB e superior ao Agar Sulfito de Bismuto no isolamento de Salmonella. Grande vantagem adicional desse meio é que as colônias de Salmonella apresentam-se facilmente identificáveis.

For the isolation of Salmonella from a variety of sources many different culture media were used. One of them, the Xylose Lysine Brilliant Green Agar medium, was employed to evaluate it in relation to the other selective-indicator media most commonly used in the isolation of these microorganisms. The results showed that Xylose Lysine Brilliant Green Agar was inferior to SS Agar and Brilliant Green Agar, slightly superior to EMB Agar, and superior to Bismuth Sulfite Agar for the isolation of Salmonella. Its great advantage is that it permits easy identification of the Salmonella colonies.

Ao pesquisar-se a presença de Salmonella a partir de materiais diversos, foram empregados vários meios de cultura e entre eles o meio Agar Xilose Lisina Verde Brilhante, com a finalidade de avaliá-lo em relação a outros meios seletivo-indicadores mais comumente empregados no isolamento desses microrganismos. Os resultados mostraram que o meio Agar Xilose Lisina Verde Brilhante foi inferior aos Agar SS e Agar Verde Brilhante, ligeiramente superior ao Agar EMB e superior ao Agar Sulfito de Bismuto no isolamento de Salmonella. Grande vantagem adicional desse meio é que as colônias de Salmonella apresentam-se facilmente identificáveis.

For the isolation of Salmonella from a variety of sources many different culture media were used. One of them, the Xylose Lysine Brilliant Green Agar medium, was employed to evaluate it in relation to the other selective-indicator media most commonly used in the isolation of these microorganisms. The results showed that Xylose Lysine Brilliant Green Agar was inferior to SS Agar and Brilliant Green Agar, slightly superior to EMB Agar, and superior to Bismuth Sulfite Agar for the isolation of Salmonella. Its great advantage is that it permits easy identification of the Salmonella colonies.

Foi desenvolvido um meio modificado de cultura para isolamento e caracterização de enterobactérias, visando especialmente salmonelas fermentadoras da lactose. No chamado "Meio modificado" as colônias das duas estirpes de Salmonella (lactose positivas e lactose negativas) apresentam a morfologia idêntica, o que não ocorre quando são empregados os meios rotineiros à base de lactose, para isolamento de enterobactérias. Esse meio é uma modificação do meio de Hektoen Enteric Agar, do qual retirou-se lactose e adicionou-se xilose e L-lisina. Foi verificado que há possibilidade de diferenciar-se os diversos grupos de enterobactérias, empregando um meio de cultura sem lactose e usando como sistema diferenciador xilose e L-lisina. O meio modificado foi também avaliado quantitativamente comparando o seu poder enriquecedor ou inibitório, ao dos meios de Hektoen Enteric Agar, Brilliant Green Agar e SS Agar para diferentes grupos de enterobactérias.

A modified culture medium was developed for the purpose of isolating and characterizing the enterobacterias, giving special attention to the Salmonella strains that ferment lactose. In this "Modified Medium" the colonies of the two strains of Salmonella show a morphological similarity. This does not occur with other culture media of enterobacteria, in which the basic carbohydrate is lactose. The Modified Medium is a modification of the Enteric Agar in which the lactose was substituted by xilose and L-lisine. It was verified that there is a possibility of differentiating between the different groups of enterobacteria by using a culture medium with no lactose and using xilose L-lisina as a differentiating system. The Modified Medium was also evaluated quantitatively comparing its enriching or inhibiting power with the Hektoen Enteric Agar, Brilliant Green Agar and the SS Agar media in relation to the different groups of enterobacteria.

Foi desenvolvido um meio modificado de cultura para isolamento e caracterização de enterobactérias, visando especialmente salmonelas fermentadoras da lactose. No chamado "Meio modificado" as colônias das duas estirpes de Salmonella (lactose positivas e lactose negativas) apresentam a morfologia idêntica, o que não ocorre quando são empregados os meios rotineiros à base de lactose, para isolamento de enterobactérias. Esse meio é uma modificação do meio de Hektoen Enteric Agar, do qual retirou-se lactose e adicionou-se xilose e L-lisina. Foi verificado que há possibilidade de diferenciar-se os diversos grupos de enterobactérias, empregando um meio de cultura sem lactose e usando como sistema diferenciador xilose e L-lisina. O meio modificado foi também avaliado quantitativamente comparando o seu poder enriquecedor ou inibitório, ao dos meios de Hektoen Enteric Agar, Brilliant Green Agar e SS Agar para diferentes grupos de enterobactérias.

A modified culture medium was developed for the purpose of isolating and characterizing the enterobacterias, giving special attention to the Salmonella strains that ferment lactose. In this "Modified Medium" the colonies of the two strains of Salmonella show a morphological similarity. This does not occur with other culture media of enterobacteria, in which the basic carbohydrate is lactose. The Modified Medium is a modification of the Enteric Agar in which the lactose was substituted by xilose and L-lisine. It was verified that there is a possibility of differentiating between the different groups of enterobacteria by using a culture medium with no lactose and using xilose L-lisina as a differentiating system. The Modified Medium was also evaluated quantitatively comparing its enriching or inhibiting power with the Hektoen Enteric Agar, Brilliant Green Agar and the SS Agar media in relation to the different groups of enterobacteria.

Admitida uma baixa freqüência de Salmonella com base em verificações anteriores em casos de diarréia aguda na cidade de Araraquara, S. Paulo, realizou-se uma investigação com um esquema ampliado para o isolamento de Salmonella a partir de 47 casos de gastroenterite infantil, 51 amostras de fezes de animais e 50 amostras de carnes e vísceras de animais destinados a alimentação. Foram isoladas Salmonella em 6,3% dos casos de gastroenterite, 5,8% de fezes de animais e 8,0% de amostras de alimentos, nesse último caso verificando-se a contaminação exclusivamente em fígado de porco, senão negativos todos os resultados de carne e vísceras de bovinos. Os sorotipos isolados corresponderam, em ordem decrescente de freqüência a S. anatum, S. derby e S. daytona. Nas gastroenterites infantis a freqüência de Shigella (12,7%) foi duas vezes superior à de Salmonella (6,3%).

After some observations, which indicated a low prevalence of Salmonella infections in the area of Araraquara, S. Paulo, an extended schedule of enrichment and isolation media were applied for investigating the presence of Salmonella organisms in 47 fecal specimens from infantile gastroenterites, 51 stool specimens from animais and 50 food samples of animal origin. Salmonella isolates were obtained in 6,3% of the g astro enter itis cases; 5,8% from animal stool cultures and 8,0% from food stuffs. In the last case only pork liver gave positive results, with no isolations being achieved from beef Products. S. anatum, S. derby and S. daytona were found in descendiny order of frequency. As related to the gastroenteritis cases Shigella organisms were twice as frequent than the Salmonella.