RESUMO
The diagnosis of bovine tuberculosis aims to identify the immune response against mycobacterial antigens. Although Single Intradermal Comparative Cervical Tuberculin test (SICCT) is broadly used for first identification of the disease, the performance of ELISAs has been investigated for diagnosis improvement. The present study expected to find out the influence of intradermal skin tests on the results of ELISAs using the recombinant proteins MPB70 and MPB83 as antigens on cows from a naturally infected herd. Results were analyzed by the F-test, Mann-Whitney and Friedman tests Although comparable to both proteins, results showed that positive animals presented a tendency of augment reactivity to MPB70, representing a tendency for a booster effect, but not to MPB83.(AU)
O diagnóstico da tuberculose bovina baseia-se na identificação da resposta imune do animal frente aos antígenos de Mycobacterium bovis. Embora o teste intradérmico comparativo cervical seja o mais empregado como primeiro teste diagnóstico, outras técnicas, como ELISA, tem sido investigadas para aumentar a detecção de animais infectados. O presente estudo analisou se os testes intradérmicos influenciariam os resultados de ELISAs que utilizaram as proteínas MPB70 e MPB83 como antígenos de captura em um rebanho naturalmente infectado. Os resultados foram analisados por meio de testes estatísticos de comparação e correlação de resultados: teste-F, Mann-Whitney e Friedman. O desempenho de ambos os ELISAs foi comparável; no entanto, os resultados demonstraram que entre os animais positivos, houve um aumento de reatividade ao MPB70, dado este que não foi observado junto ao ELISA-MPB83.(AU)
Assuntos
Animais , Feminino , Bovinos , Tuberculose Bovina/diagnóstico , Ensaio de Imunoadsorção Enzimática/veterinária , Testes Intradérmicos/veterinária , Antígenos de Bactérias , Técnicas e Procedimentos Diagnósticos/veterináriaRESUMO
The diagnosis of bovine tuberculosis aims to identify the immune response against mycobacterial antigens. Although Single Intradermal Comparative Cervical Tuberculin test (SICCT) is broadly used for first identification of the disease, the performance of ELISAs has been investigated for diagnosis improvement. The present study expected to find out the influence of intradermal skin tests on the results of ELISAs using the recombinant proteins MPB70 and MPB83 as antigens on cows from a naturally infected herd. Results were analyzed by the F-test, Mann-Whitney and Friedman tests Although comparable to both proteins, results showed that positive animals presented a tendency of augment reactivity to MPB70, representing a tendency for a booster effect, but not to MPB83.
O diagnóstico da tuberculose bovina baseia-se na identificação da resposta imune do animal frente aos antígenos de Mycobacterium bovis. Embora o teste intradérmico comparativo cervical seja o mais empregado como primeiro teste diagnóstico, outras técnicas, como ELISA, tem sido investigadas para aumentar a detecção de animais infectados. O presente estudo analisou se os testes intradérmicos influenciariam os resultados de ELISAs que utilizaram as proteínas MPB70 e MPB83 como antígenos de captura em um rebanho naturalmente infectado. Os resultados foram analisados por meio de testes estatísticos de comparação e correlação de resultados: teste-F, Mann-Whitney e Friedman. O desempenho de ambos os ELISAs foi comparável; no entanto, os resultados demonstraram que entre os animais positivos, houve um aumento de reatividade ao MPB70, dado este que não foi observado junto ao ELISA-MPB83.
Assuntos
Animais , Feminino , Bovinos , Antígenos de Bactérias , Ensaio de Imunoadsorção Enzimática/veterinária , Testes Intradérmicos/veterinária , Tuberculose Bovina/diagnóstico , Técnicas e Procedimentos Diagnósticos/veterináriaRESUMO
As tuberculosis is still a worldwide infection and buffalo breeding represents an important economic activity in various countries, the purpose of this study was to employ an enzyme-linked immunosorbent assay (ELISA) using MPB70 as a capture antigen for the diagnosis of naturally occurring tuberculosis in water buffaloes in Brazil. After the introduction of newly acquired cattle onto a tuberculosis (TB) free farm, an outbreak of TB was recorded in a mixed herd comprising water buffaloes (21) and cattle (46). The entire herd was tested by intradermal tuberculin injection (ITT) and positive animals were slaughtered and tested by culture, polymerase chain reaction (PCR), and ELISA. From the 21 buffaloes sampled, three were reactive by ITT. All the three had positive culture and ELISA, while PCR was positive in two of them. Besides that, one ITT-negative buffalo was slaughtered and presented positive results by both culture and ELISA, and was considered as anergic. Although there were only few animals, those findings demonstrate the diagnostic usefulness of an MPB70-ELISA to correctly detect Mycobacterium bovis tuberculosis in water buffaloes.