Qualitative and Quantitative Determination and Resistance Patterns of Salmonella from Poultry Carcasses.

Poultry products are important in the transmission of zoonotic pathogens, mainly Salmonella. This genus causes millions of foodborne diseases worldwide every year. Cross-contamination by food sources in human cases of salmonellosis and the increase in resistant strains have become important issues. A qualitative and quantitative Salmonella detection method was utilized in a poultry slaughterhouse in São Paulo State, Brazil. We collected 33 samples from different batches of carcasses. Each sample was analyzed at three process points: postbleeding, postdefeathering, and postchilling. A fourth point, retail simulation, was added to simulate retail market storage at 5°C for 72 h. The qualitative methods revealed 100% (33 samples) contamination at postbleeding, 39% (13 samples) contamination at postdefeathering, 58% (19 samples) contamination at postchilling, and 30% (10 samples) contamination at the retail simulation. The quantitative results, determined by the most-probable-number (MPN) technique, ranged from <0.03 to >2,400 MPN/g. We identified 23 Salmonella serovars; the most prevalent were Mbandaka, Senftenberg, and Enteritidis. Resistance to nalidixic acid was significantly more common (P < 0.05) than resistance to other antimicrobial agents. Five multidrug-resistant strains were identified. This study contributes important epidemiological data and demonstrates the need to improve sanitary conditions in slaughterhouses.

Cleaning conveyor belts in the chicken-cutting area of a poultry processing plant with 45°c water.

Conveyor belts are widely used in food handling areas, especially in poultry processing plants. Because they are in direct contact with food and it is a requirement of the Brazilian health authority, conveyor belts are required to be continuously cleaned with hot water under pressure. The use of water in this procedure has been questioned based on the hypothesis that water may further disseminate microorganisms but not effectively reduce the organic material on the surface. Moreover, reducing the use of water in processing may contribute to a reduction in costs and emission of effluents. However, no consistent evidence in support of removing water during conveyor belt cleaning has been reported. Therefore, the objective of the present study was to compare the bacterial counts on conveyor belts that were or were not continuously cleaned with hot water under pressure. Superficial samples from conveyor belts (cleaned or not cleaned) were collected at three different times during operation (T1, after the preoperational cleaning [5 a.m.]; T2, after the first work shift [4 p.m.]; and T3, after the second work shift [1:30 a.m.]) in a poultry meat processing facility, and the samples were subjected to mesophilic and enterobacterial counts. For Enterobacteriaceae, no significant differences were observed between the conveyor belts, independent of the time of sampling or the cleaning process. No significant differences were observed between the counts of mesophilic bacteria at the distinct times of sampling on the conveyor belt that had not been subjected to continuous cleaning with water at 45°C. When comparing similar periods of sampling, no significant differences were observed between the mesophilic counts obtained from the conveyor belts that were or were not subjected to continuous cleaning with water at 45°C. Continuous cleaning with water did not significantly reduce microorganism counts, suggesting the possibility of discarding this procedure in chicken processing.

Identification of pathogens and virulence profile of Rhodococcus equi and Escherichia coli strains obtained from sand of parks.

The identification of pathogens of viral (Rotavirus, Coronavirus), parasitic (Toxocara spp.) and bacterial (Escherichia coli, Salmonella spp., Rhodococcus equi) origin shed in feces, and the virulence profile of R. equi and E. coli isolates were investigated in 200 samples of sand obtained from 40 parks, located in central region of state of Sao Paulo, Brazil, using different diagnostic methods. From 200 samples analyzed, 23 (11.5%) strains of R. equi were isolated. None of the R. equi isolates showed a virulent (vapA gene) or intermediately virulent (vapB gene) profiles. Sixty-three (31.5%) strains of E. coli were identified. The following genes encoding virulence factors were identified in E. coli: eae, bfp, saa, iucD, papGI, sfa and hly. Phylogenetic classification showed that 63 E. coli isolates belonged to groups B1 (52.4%), A (25.4%) and B2 (22.2%). No E. coli serotype O157:H7 was identified. Eggs of Toxocara sp. were found in three parks and genetic material of bovine Coronavirus was identified in one sample of one park. No Salmonella spp. and Rotavirus isolates were identified in the samples of sand. The presence of R. equi, Toxocara sp, bovine Coronavirus and virulent E. coli isolates in the environment of parks indicates that the sanitary conditions of the sand should be improved in order to reduce the risks of fecal transmission of pathogens of zoonotic potential to humans in these places.

Listeria monocytogenes, E. coli O157, Salmonella spp. e microrganismos indicadores em carcaças bovinas para exportação / Listeria monocytogenes, E. coli O157, Salmonella spp., micro-organism indicators in export cattle carcasses

Foram colhidas amostras de 100 carcaças em um frigorífico exportador, localizado no interior do estado de São Paulo, amostradas ao longo de um ano, por meio do método de esponjas, aplicado na região do peito do animal. As amostras foram colhidas em três pontos, denominados A, B e C, sendo cada carcaça amostrada nos três pontos, localizados nas etapas: pós-sangria (A); pós-esfola (B) e pós-lavagem (C). Foram realizadas pesquisas de Listeria sp., E. coli O157, Salmonella spp. e microrganismos indicadores (Petrifilms® AC, EC e EB). Não foram isolados Listeria ou E. coli O157 em nenhuma das 300 amostras. Salmonella spp. foi isolada em nove, sendo oito no ponto A e uma no ponto B. Para mesófilos, as contagens variaram de 0 a 6,8 log UFC/cm², para coliformes totais, de 0 a 4,57 log UFC/cm², e para E. coli, de 0 a 4,38 log UFC/cm². Diante dos resultados obtidos e em comparação com a literatura, conclui-se que o estabelecimento estudado apresenta qualidade, tanto sanitária (devido às baixas prevalências dos patógenos) quanto higiênica (devido à acentuada diminuição da carga microbiana de indicadores ao longo da linha).

Samples were collected from 100 carcasses in a slaughterhouse exporter, located within the State of São Paulo, sampled over a year through the sponge method, applied to the chest of the animal. Samples were taken at three points, denominated A, B and C, each carcass sampled at three points located in the following steps: after bleeding (A) after skinning (B) and after washing (C). Research was conducted for Listeria sp., E. coli O157, Salmonella spp. and Micro-organism (Petrifilms ® AC, EC and EB). Listeria or E. coli O157 were not isolated in any of the 300 samples. Salmonella spp. was isolated in nine, eight at point A and one at point B. For Mesophiles, scores ranged from 0 to 6.8 log UFC/cm²; for Total coliforms, 0 to 4.57 log UFC/cm² and E. coli from 0 to 4.38 log UFC/cm². With the results obtained and compared with the literature, it is concluded that the establishment in this study has both sanitary quality (due to the low prevalence of pathogens) and hygienic quality (due to the sharp decrease in the microbial load of indicators along the line.

Identification of pathogens and virulence profile of Rhodococcus equi and Escherichia coli strains obtained from sand of parks

The identification of pathogens of viral (Rotavirus, Coronavirus), parasitic (Toxocara spp.) and bacterial (Escherichia coli, Salmonella spp., Rhodococcus equi) origin shed in feces, and the virulence profile of R. equi and E. coli isolates were investigated in 200 samples of sand obtained from 40 parks, located in central region of state of Sao Paulo, Brazil, using different diagnostic methods. From 200 samples analyzed, 23 (11.5%) strains of R. equi were isolated. None of the R. equi isolates showed a virulent (vapA gene) or intermediately virulent (vapB gene) profiles. Sixty-three (31.5%) strains of E. coli were identified. The following genes encoding virulence factors were identified in E. coli: eae, bfp, saa, iucD, papGI, sfa and hly. Phylogenetic classification showed that 63 E. coli isolates belonged to groups B1 (52.4%), A (25.4%) and B2 (22.2%). No E. coli serotype O157:H7 was identified. Eggs of Toxocara sp. were found in three parks and genetic material of bovine Coronavirus was identified in one sample of one park. No Salmonella spp. and Rotavirus isolates were identified in the samples of sand. The presence of R. equi, Toxocara sp, bovine Coronavirus and virulent E. coli isolates in the environment of parks indicates that the sanitary conditions of the sand should be improved in order to reduce the risks of fecal transmission of pathogens of zoonotic potential to humans in these places.

Microbiological evaluation of chicken carcasses in an immersion chilling system with water renewal at 8 and 16 hours.

Since 2004, Brazil has been the leading exporter of chicken. Because of the importance of this sector in the Brazilian economy, food safety must be ensured by control and monitoring of the production stages susceptible to contamination, such as the chilling process. The goal of this study was to evaluate changes in microbial levels on chicken carcasses and in chilling water after immersion in a chilling system for 8 and 16 h during commercial processing. An objective of the study was to encourage discussion regarding the Brazilian Ministry of Agriculture Livestock and Food Supply regulation that requires chicken processors to completely empty, clean, and disinfect each tank of the chilling system after every 8-h shift. Before and after immersion chilling, carcasses were collected and analyzed for mesophilic bacteria, Enterobacteriaceae, coliforms, and Escherichia coli. Samples of water from the chilling system were also analyzed for residual free chlorine. The results do not support required emptying of the chiller tank after 8 h; these tanks could be emptied after 16 h. The results for all carcasses tested at the 8- and 16-h time points indicated no significant differences in the microbiological indicators evaluated. These data provide both technical and scientific support for discussing changes in federal law regarding the management of immersion chilling water systems used as part of the poultry processing line.

Microbiological quality of spices marketed in the city of Botucatu, São Paulo, Brazil.

The aim of this work was to assess the microbiological quality of spices sold in Botucatu, São Paulo, Brazil. A total of 233 samples were analyzed for mesophilic bacteria, thermotolerant coliforms, Bacillus cereus, Staphylococcus aureus, and Salmonella. Data showed that 21 and 5.6% of these samples were not in agreement with the standards of Brazilian law, due to an excess of coliforms and to the presence of Salmonella, respectively. Black pepper and cumin exhibited the lowest microbiological quality, whereas bay leaf showed the highest quality. It was concluded that the seasonings possessed poor microbiological quality, and new alternatives should be taken in the primary production in order to improve this quality. Irradiation may also be a tool to assure the safety of these products.

Avaliação do teste do anel em leite na vigilância epidemiológica da brucelose bovina em rebanhos e em laticínios / Evaluation of the ring test in an epidemiological surveillance of bovine brucellosis in herds and dairies

Analisaram-se 464 amostras individuais de leite e 54 amostras de leite de latões, oriundos de leite dos mesmos animais, por meio do teste do anel do leite (TAL) visando à sua aplicação no diagnóstico individual e de rebanhos da brucelose bovina. Foram também avaliadas 464 amostras de soro sangüíneo por meio de provas do antígeno tamponado acidificado (ATA), soroaglutinação lenta em tubos (SAL) e 2-mercaptoetanol (2-ME), todas para brucelose. Cento e vinte e três amostras (26,5 por cento) testadas pelo TAL apresentaram resultados positivos. Dessas, 30 resultaram positivas ao ATA, 28 ao ATA, à SAL e ao 2-ME e 18 à SAL. Das amostras positivas ao TAL, 95 pertenciam a animais sorologicamente negativos ao 2-ME, caracterizando 77,2 por cento (95/123) das reações falso-positivas; dos resultados negativos ao TAL, 4 pertenciam a animais sorologicamente positivos, caracterizando 1,2 por cento (4/341) de reações falso-negativas no TAL individual. Das 54 amostras de leite de latões analisadas pelo TAL, 17 foram consideradas positivas, das quais uma foi caracterizada como falso-positivo, pois todos os animais que a compunham foram negativos ao 2-ME. De 37 latões considerados negativos ao TAL, três continham leite de animais positivos ao 2-ME, caracterizando 8,1 por cento de falso-negativos. O TAL individual demonstrou elevado percentual de resultados falso-positivos, enquanto o TAL em amostras de leite obtidas em latões detectou 84,2 por cento de latões contaminados e 75 por cento de rebanhos infectados.

The ring test (RT) was analyzed regarding its application for the individual and herd bovine brucellosis diagnoses. Individual samples of milk from 464 cows and 54 composite samples of milk bucket from these animals were evaluated. The results were analyzed considering the serological results obtained by the rose bengal (RBT), tube agglutination (TAT) and 2-mercaptoethanol (2-ME) tests. From the 464 individual milk samples analyzed by the RT, 123 (26.5 percent) presented positive results. From those, 30 were positive only to the RBT, 28 by the RBT/TAT/2-ME and 18 by the TAT. From the 123 positive samples by the RT, 95 came from the 2-ME seronegative animals, characterizing 77.2 percent of false-positive reactions and 4/341 negative reactions came from the seropositive animals, characterizing 1.2 percent of false-negative reactions in the individual RT. From the 54 samples of compositive milk analyzed by the RT, 17 were positive. From these positive samples, one was considered false positive since all the animals that composed it were negative by the 2-ME. Three of the composite milk samples that were negative to RT(3/37) were constituted by milk from positive animals, characterizing 8.1 percent of false-negative results by the RT. The individual RT showed high percentage of false-positive results, while the RT in samples from bucket detected 84.2 percent of the contaminated milk and 75 percent of the infected herds.