Perfil epidemiológico da cisticercose bovina e suína em três regiões do estado de Minas Gerais, Brasil / Epidemiological profile of bovine and swine cysticercosis in three regions of Minas Gerais State, Brazil

Com o objetivo de avaliar a situação epidemiológica da cisticercose suína e bovina na zona rural de cinco municípios, distribuídos em três distintas regiões do estado de Minas Gerais, foi determinada a prevalência das cisticercoses bovina e suína nas propriedades rurais e os principais fatores de risco que poderiam favorecer a transmissão e manutenção da doença nas referidas propriedades. A pesquisa abrangeu 388 propriedades, localizadas em 91 diferentes comunidades rurais, sendo coletadas 1.792 amostras de sangue bovino e 554 de suíno. Além da avaliação das referidas amostras laboratoriais (ELISA indireto e imunoblot), também foram analisados os dados obtidos da aplicação de um questionário para cada propriedade, no qual constava as informações sobre as condições socioeconômicas, higiênico-sanitárias e as relacionadas ao sistema de criação animal. A prevalência da cisticercose variou de 0,3 a 5,9% nos bovinos e de 0 a 2,8% nos suínos criados artesanalmente nesses municípios pesquisados. Os principais fatores de risco de transmissão identificados foram a fonte de água consumida, a origem da carne, a natureza do município e da região, para a cisticercose bovina, e o destino do esgoto e o sistema de criação, para a cisticercose suína.(AU)

In order to evaluate the epidemiological situation of porcine and bovine cysticercosis in the rural area of five municipalities, distributed in three different regions of the state of Minas Gerais, Brazil, the prevalence of bovine and porcine cysticercosis was determined in the rural properties as well as the main risk factors that may favor the transmission and maintenance of the disease in these properties. The research covered 388 farms, located in 91 different rural communities, with 1,792 samples of bovine blood and 554 of swine collected. In addition to the evaluation of these laboratory samples (indirect ELISA and Imunoblot), the data obtained from the application of a questionnaire for each property were also analyzed, with information on socioeconomic, hygienic-sanitary and animal-related conditions. The prevalence of cysticercosis ranged from 0.3 to 5.9% in cattle and from 0 to 2.8% in the pigs raised in these municipalities. Among the main risk factors for transmission of bovine cysticercosis were the source of water consumed, the origin of the meat, the nature of the municipality and the region. Regarding the pigs, risk factors were the sewage disposal and animal management system.(AU)

Diagnóstico do complexo teníase-cisticercose bovina em São João Evangelista, Minas Gerais, Brasil / Diagnosis of Bovine Taeniasis-Cysticercosis Complex in São João Evangelista, Minas Gerais, Brazil

Com o objetivo de diagnosticar a situação do complexo teníase-cisticercose bovina em Minas Gerais, Brasil, foi selecionado o município de São João Evangelista, onde foram coletadas amostras de sangue de 339 bovinos em 15 propriedades rurais, sorteadas aleatoriamente. Em cada propriedade, foi aplicado um questionário socioeconômico para a análise de fatores que favorecem a manutenção do complexo teníase-cisticercose bovina. Foi realizado também o diagnóstico de teníase humana por meio de exame coproparasitológico dos habitantes das propriedades. Encontrou-se a prevalência de 4,1% para cisticercose bovina e a frequência de 2,94% para teníase humana. Entre os fatores de risco para a manutenção do complexo teníase-cisticercose analisados, foi observada uma relação estatisticamente significativa (P=0,042) entre a ocorrência de cisticercose bovina e a ingestão de carne malpassada pelos entrevistados. Concluiu-se que a cisticercose bovina está presente no município de São João Evangelista, MG, em índices considerados endêmicos, sendo o consumo de carne malpassada e não inspecionada o principal fator de risco para a manutenção do complexo teníase-cisticercose, o que reforça a necessidade da adoção de medidas de controle com contínua vigilância epidemiológica e sanitária.

In order to diagnose the situation of bovine taeniasis-cysticercosis complex in the state of Minas Gerais, Brazil, the city of São João Evangelista was selected, and blood samples were collected from 339 cattle in 15 randomly selected farms. A socioeconomic questionnaire was filled in each property for the analysis of the factors that favor the maintenance of the taeniasis-cysticercosis complex. Additionally, there was the diagnosis of human taeniasis verified by stool examinations of the properties' inhabitants. A prevalence of 4.1% for bovine cysticercosis and the frequency of 2.94% for human taeniasis were found. Among the risk factors, a statistically significant relation (p = 0.042) was found between the occurrence of bovine cysticercosis and the ingestion of undercooked meat. It was concluded that bovine cysticercosis is broadly distributed in the city of São João Evangelista, with rates considered endemic, being the consumption of raw and not-inspected meat the main risk factors for the maintenance of complex taeniasis-cysticercosis, reinforcing the need to adopt control measures with continuous epidemiological and health surveillance.

Relevant peptides of Taenia crassiceps for the diagnosis of bovine cysticercosis by immunoblot / Peptídeos relevantes de Taenia crassiceps para o diagnóstico da cisticercose bovina pelo immunoblot

Given the limited knowledge about the diagnosis of bovine cysticercosis by immunoblot, the aim of this study was to assess the applicability of this test, identifying key peptides with diagnostic value. Immunoblot assays were performed using total larval antigen of Taenia crassiceps and 60 sera of positive bovines for cysticercosis (30 naturally and 30 experimentally infected with T. saginata eggs), 30 sera of negative bovines for cysticercosis and 30 sera of bovines with other diseases (fascioliasis, hydatidosis and tuberculosis). The peptides of greater diagnostic importance, in descending order of accuracy (%), were as follows: 6-8kDa (90.8%), 129-143kDa (74.2%), 99-105kDa (71.7%) and 14-19kDa (71.1%). Cross-reactions, due to fascioliasis and hydatidosis, were observed in the four intervals of peptides highlighted. The results demonstrate that the total antigen of T. crassiceps has peptides with a high diagnostic potential; therefore, the immunoblot is useful in the diagnosis of bovine cysticercosis.

Tendo em vista o conhecimento limitado sobre o diagnóstico da cisticercose bovina pelo immunoblot, o objetivo deste trabalho foi avaliar a aplicabilidade desse teste, identificando os principais peptídeos com valor diagnóstico. Foram realizados ensaios de immunoblot, utilizando antígeno total de larva de Taenia crassiceps e 60 soros de bovinos positivos para a cisticercose (30 naturalmente e 30 experimentalmente infectados com ovos de T. saginata), 30 soros de bovinos negativos para a cisticercose e 30 soros de bovinos com outras patologias (fasciolose, hidatidose e tuberculose). Os peptídeos de maior importância diagnóstica, em ordem decrescente de acurácia (%), foram os seguintes: 6-8 kDa (90,8%), 129-143 kDa (74,2%), 99-105 kDa (71,7%) e 14-19 kDa (71,1%). Reações cruzadas, em decorrência da fasciolose e hidatidose, foram observadas nos quatro intervalos de peptídeos ressaltados. Os resultados demonstram que o antígeno total de T. crassiceps possui peptídeos com alto potencial diagnóstico, sendo, portanto, o immunoblot útil no diagnóstico da cisticercose bovina.

Ovicidal activity of different concentrations of Pochonia chlamydosporia chlamydospores on Taenia taeniaeformis eggs.

Three concentrations of chlamydospores of the nematophagous fungus Pochonia chlamydosporia (1000, 10,000 and 20,000 per Petri dish) were evaluated in vitro on Taenia taeniaeformis eggs. Chlamydospores at each concentration were cultured in two different media: 2% water-agar (2%WA) and 2% corn-meal-agar (2%CMA). Taenia taeniaeformis eggs were plated in each chlamydospore concentration in 2%WA and 2%CMA (treated groups) and without fungus (control group). Eggs were removed from each Petri dish at intervals of 7, 14 and 21 days and classified according to ovicidal activity (type 1, type 2 and type 3 effects). Plates containing 2%CMA showed the highest percentages for type 3 effect (81.3%) on the 21st day of observation. A difference (P < 0.01) between the media 2%WA and 2%CMA for type 1 effect was observed only at a concentration of 1000 chlamydospores on the 7th day. There were differences (P < 0.01) between 2%WA and 2%CMA on the 14th and 21st days, at the concentration of 20,000 chlamydospores, for type 1 and type 3 effects. Regression curves for type 3 effect in 2%WA and 2%CMA at the tested concentrations showed higher ovicidal activity with increasing chlamydospore concentrations. Results indicate that, at concentrations of 1000, 10,000 and 20,000 per Petri dish, chlamydospores of P. chlamydosporia effectively destroyed T. taeniaeformis eggs and can be considered a potential biological control agent for this cestode.

Evaluation of a polymerase chain reaction protocol for the detection of Salmonella species directly from superficial samples of chicken carcasses and preenrichment broth.

Chicken meat is an important vehicle of foodborne pathogens, such as Salmonella spp., and demands a systematic control of microbiological contamination during industrial processing. This control occurs by the adoption of quality control systems in slaughters based on the microbiological investigation on hygiene indicators and pathogens, requiring the development of fast, trustable, and precise methodologies. The objective of this study was to compare the Salmonella spp. conventional methodology to a protocol of PCR in chicken carcass surface samples. The PCR protocol was developed directly from the collected samples and from preenrichment broth before and after incubation. The obtained results were compared by chi(2) and McNemar tests (P < 0.05), and the values of concordance, sensitivity, and specificity of PCR variations were calculated considering the conventional methodology as a parameter. The obtained results indicated that although some similarities between the methodologies were observed when positive results were considered (P > 0.05), the PCR developed from preenrichment after incubation presented significant differences from all the other methodologies (P < 0.05). Wide variations were observed in the PCR performance for Salmonella spp. detection in chicken carcasses, which can be due to intrinsic factors inherent to the achievement of this food. Further studies are necessary to elucidate the applicability of the PCR as a tool for microbiological monitoring in quality control systems for chicken processing.

Pontos críticos de controle de Salmonella spp. no abate de frangos / Critical control points for Salmonella spp. in poultry slaughter

Avaliou-se a presença de Salmonella spp. em esfregaços superficiais em 135 carcaças de frangos, coletadas em cinco diferentes fases do abate, utilizando os métodos de microbiologia convencional, reação em cadeia de polimerase (PCR) e imunoanálise. Os três métodos resultaram em tendência semelhante de detecção de Salmonella spp. nas carcaças de frango, ao longo da linha de abate. A maior frequência de Salmonella spp. foi determinada após o chuveiro de lavagem das carcaças, localizado entre a evisceração e o pré-resfriamento. Vinte (14,8 por cento) esfregaços foram determinados pela metodologia convencional, 52 (38,5 por cento) pela PCR e 66 (48,8 por cento) pela imunoanálise. A menor contaminação foi encontrada na saída do pré-resfriamento, com frequências de 3,7 por cento, 0 por cento e 16,7 por cento, respectivamente. Salmonella spp. foi encontrada em todas as fases de abate, mostrando a importância do monitoramento de diferentes pontos críticos de controle eventualmente identificados no abate de frangos.

The presence of Salmonella spp. in superficial swabs collected from 135 chicken carcasses in five different slaugther steps using the conventional microbiology, PCR, and immunoanalysis methods was evaluated. The three methods presented similar tendency to detect Salmonella spp. in the chicken carcasses along the slaugther line. The highest frequency of Salmonella spp. was found after the shower, located between the evisceration and the chiller. Twenty (14.8 percent) swabes were determined by the conventional methodology, 52 (38.9 percent) by the PCR, and 66 (48.9 percent) by the immunoanalysis. The lowest contamination was found after chiller tank, where the frequencies were 5 (3.7 percent), 0 (0 percent), and 24 (16.7 percent), respectively. Salmonella spp. was found in all the slaugther steps. This shows the importance for monitoring different CCP (Control Critical Point) in the poultry slaughterhouses.

Antígenos de larva de Taenia solium em ELISA para diagnóstico da cisticercose bovina / Taenia solium metacestode antigens in ELISA for the diagnosis of bovine cysticercosis

Foram avaliados alguns parâmetros inerentes ao ELISA, por meio de ensaios de reatividade de soros-controle positivos e negativos para a cisticercose bovina com relação a três tipos de antígenos de larva de Taenia solium: total, de escólex e de membrana. As concentrações de antígeno de 0,25; 0,5; 1; 2 e 4µg por orifício, e as diluições de soro de 1:25, 1:50, 1:100 e 1:200, foram os parâmetros que menos influenciaram no desempenho do teste. A substância bloqueadora, o leite desnatado e as diluições de conjugado, 1:1.250, 1:2.500 e 1:5.000, representaram os melhores indicadores de desempenho do teste. Concluiu-se que essa combinação de critérios deve ser considerada no diagnóstico da cisticercose bovina, em atividades de rotina ou de padronização do referido teste, considerando os três antígenos de larva de T. solium estudados.

Some parameters of ELISA were evaluated using positive and negative bovine sera for cysticercosis and three types of antigens of Taenia solium larvae: total, scolex and membrane. The antigen concentrations (0.25; 0.5; 1; 2 and 4µg/well) and the serum dilutions (1:25, 1:50, 1:100 and 1:200) were the parameters that influenced less the test performance; while blocking substance, skimmed milk, and conjugate dilutions, 1:1.250, 1:2.500 and 1:5.000 were the best indexes of the test performance. It was concluded that this combination of criteria should be considered in the diagnosis of bovine cysticercosis, in routine diagnosis and for the ELISA test standardization.

Evaluation of the ELISA test for the antibody detection in cattle naturally and experimentally infected with Cysticerccus bovis.

The ELISA test was evaluated for the diagnosis of bovine cysticercosis using heterologous antigens from the larvae of T. solium and T. crassiceps, by using different types of positive and negative control sera, to allow a broader analysis of the results. The ELISA test showed low sensitivity under natural conditions of bovine cysticercosis manifestation, but high rates (up to 90%) under experimental conditions. The high specificity of the test (81-100%) made evident its capacity to differentiate cysticercosis from other bovine diseases. No difference in performance was found among the antigens studied. It was concluded that the ELISA test has deficiencies in detecting anti-cysticercosis antibodies of animals at slaughterhouse. However, it can be useful in detecting experimentally infected animals and differentiating cysticercosis from other bovine diseases.

Aplicação da técnica de PCR na detecção de Yersinia enterocolitica em suínos abatidos sem inspeção / PCR technique application in Yersinia enterocolitica detection in non-inspected swine

Avaliou-se a contaminação de carcaças e tonsilas de suínos por Y. enterocolitica em estabelecimentos de abate não inspecionados, comparando a pesquisa microbiológica convencional com a técnica da reação em cadeia de polimerase (PCR) e o tipo de amostra analisada (de tonsila ou de carcaça), como subsídio ao monitoramento microbiano em sistemas de análise de perigos e pontos críticos de controle. Calcularam-se os custos dos dois testes. Não se detectou Y. enterocolitica pela técnica microbiológica convencional, mas, pela técnica de PCR foi possível detectar a bactéria em 40 por cento das carcaças e em 43 por cento das tonsilas, incluindo cepas patogênicas nas tonsilas. Não houve diferença entre os resultados positivos para as amostras de tonsilas e esfregaços de superfície das carcaças. A PCR apresentou-se como uma alternativa na detecção do agente e uma técnica aparentemente mais eficaz, econômica e rápida. Os resultados indicam a PCR como um importante recurso para o controle de qualidade da carne suína.

The contamination of swine carcasses and tonsils by Yersinia enterocolitica in slaughterhouses without inspection was evaluated. The conventional microbiological analysis was compared with the PCR technique of carcass or tonsil swabs, as a subsidy to the microbiological evaluation in the HACCP system. The costs of the two techniques were also calculated. Y. enterocolitica was not detected by the conventional microbiological analysis. Using the PCR, it was possible to detect this bacterium in carcass (40 percent) and tonsil (43 percent) samples. There was no difference between the positive results for the carcass and tonsil samples. The PCR showed to be a more effective, fast and economic alternative for the Y. enterocolitica detection, as compared to the conventional microbiological analysis.