PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Bastos R., Soares C.O., Elisei C., Munhoz A.L.R., Bezerra N.L., Caitano M.A.B. & Rosinha, G.M.S. 2012. [Genetic evaluation of vaccine against bovine brucellosis marketed in Brazil.] Avaliação genética das vacinas contra a brucelose bovina comercializadas no Brasil. Pesquisa Veterinária Brasileira 32(10):957-962. Faculdade de Medicina Veterinária e Zootecnia, Universidade Federal de Mato Grosso do Sul, Av. Felinto Müller 2443, Ipiranga, Campo Grande, 79070-900, MS, Brazil. E-mail: rosinha@cnpgc.embrapa.br Vaccine strains B19 and RB51 are administered to cattle for prevention against infection by Brucella abortus. However, there are reports that these vaccines can cause miscarriages. Thus, every miscarriage among vaccinated animals should be thoroughly studied to determine the cause. In Brazil, there are no records on the origin of B19 and RB51 samples used in the preparation of commercial vaccines. Therefore, a study is needed to determine possible mutations in relation to the USDA reference samples of B. abortus due to the fact that vaccine samples could revert to the virulence of the disease. The aim of the present study was to perform a genotype analysis of vaccine strains B19 and RB51 used in Brazil. The methodology was based on the genotyping of marker genes of these vaccine strains by amplification using polymerase chain reaction. The results allowed the identification of the genotype of the B19 and RB51 commercial vaccine available for use on cattle in Brazil. The absence of mutations in the samples tested confirmed the genetic quality of the vaccines and stability of genes analyzed.

• Brucella abortus brucellosis vaccine B19 brucelose

Abstract in Portuguese:

RESUMO.- Bastos R., Soares C.O., Elisei C., Munhoz A.L.R., Bezerra N.L., Caitano M.A.B. & Rosinha, G.M.S. 2012. [Genetic evaluation of vaccine against bovine brucellosis marketed in Brazil.] Avaliação genética das vacinas contra a brucelose bovina comercializadas no Brasil. Pesquisa Veterinária Brasileira 32(10):957-962. Faculdade de Medicina Veterinária e Zootecnia, Universidade Federal de Mato Grosso do Sul, Av. Felinto Müller 2443, Ipiranga, Campo Grande, 79070-900, MS, Brazil. E-mail: rosinha@cnpgc.embrapa.br A prevenção contra infecções causadas por Brucella abortus em bovinos é realizada por meio da administração das amostras vacinais B19 e RB51. Existem relatos de que estas vacinas podem causar aborto em fêmeas vacinadas. Portanto, toda a ocorrência de aborto em animais vacinados merece um estudo aprofundado sobre a causa. No Brasil, não há registro sobre a origem das amostras B19 e RB51 utilizadas na produção das vacinas comerciais. Assim, um estudo para verificar possíveis mutações em relação às amostras referência USDA B19 e USDA RB51 de B. abortus se faz necessário, devido às amostras vacinais poderem reverter a sua virulência. Objetivou-se com este estudo caracterizar genotipicamente as amostras vacinais B19 e RB51 comercializadas no Brasil. A metodologia utilizada foi a genotipagem de genes marcadores destas amostras vacinais, por meio da amplificação pela reação em cadeia da polimerase. Os resultados obtidos permitiram a identificação do genótipo das vacinas comerciais B19 e RB51 disponíveis e utilizadas em bovinos no Brasil. A ausência de mutações nas vacinas testadas corrobora com a qualidade genética das mesmas, quanto à estabilidade dos genes analisados.

Abstract in English:

ABSTRACT.- Mathias L.A., Meirelles R.B. & Buchala F.G. 2007. [Stability of Brucella abortus whole cell antigen for use in the serological diagnosis of bovine brucellosis by the complement fixation test.] Estabilidade do antígeno de célula total de Brucella abortus para uso no diagnóstico sorológico da brucelose bovina pela reação de fixação de complemento. Pesquisa Veterinária Brasileira 27(1):18-22. Departamento de Medicina Veterinária Preventiva e Reprodução Animal, Faculdade de Ciências Agrárias e Veterinárias (FCAV), Universidade Estadual Paulista (Unesp), Jaboticabal, SP 14884-900, Brazil. E-mail: lmathias@fcav.unesp.br The complement fixation test is used worldwide in the confirmatory diagnosis of bovine brucellosis. For this technique the antigen is the same as the one used in the tube agglutination test. However, literature is poor in information about the stability of the whole cell Brucella antigen for use in the complement fixation test to establish a time of validity of the antigen. Hence the aim of this investigation was to evaluate the stability of this antigen under refrigeration for use in the complement fixation test. Fourteen batches of antigen prepared with Brucella abortus strain 1119/3, produced from 9 months to 23 years and 11 months before, were analysed. One hundred and sixty-seven cattle sera with varying titres of antibodies to Brucella were tested through the warm complement fixation microtechnique with five 50% haemolytic units of complement. Sera with at least 25% of complement fixation in dilution 1:4 were considered positive. The results with 13 of the antigen batches were compared with the results obtained with the batch produced 9 months before by the McNemar c2 test and kappa statistic. The oldest antigen batch gave a higher proportion of sera titres which were exactly the same observed with the 9-month-batch (90.4%), and the antigen produced 4 years and 3 months before the test gave de lowest proportion of sera with the same titre of the 9-month-antigen (73.7%). The comparison of the results after being classified as positive and negative showed that the highest proportion of agreed results was observed with the antigen produced 21 years and 4 months before (98.8%, kappa 0.98). The antigen with the lowest proportion of agreed results was the one produced 3 years and 2 months before (91.6%, kappa 0.84). The results of the study show that most sera gave very similar results with all antigen batches evaluated, and that there was no relationship between the period of antigen production and the difference in test results.

• Bovine brucellosis serological diagnosis complement fixation test

Abstract in Portuguese:

ABSTRACT.- Mathias L.A., Meirelles R.B. & Buchala F.G. 2007. [Stability of Brucella abortus whole cell antigen for use in the serological diagnosis of bovine brucellosis by the complement fixation test.] Estabilidade do antígeno de célula total de Brucella abortus para uso no diagnóstico sorológico da brucelose bovina pela reação de fixação de complemento. Pesquisa Veterinária Brasileira 27(1):18-22. Departamento de Medicina Veterinária Preventiva e Reprodução Animal, Faculdade de Ciências Agrárias e Veterinárias (FCAV), Universidade Estadual Paulista (Unesp), Jaboticabal, SP 14884-900, Brazil. E-mail: lmathias@fcav.unesp.br The complement fixation test is used worldwide in the confirmatory diagnosis of bovine brucellosis. For this technique the antigen is the same as the one used in the tube agglutination test. However, literature is poor in information about the stability of the whole cell Brucella antigen for use in the complement fixation test to establish a time of validity of the antigen. Hence the aim of this investigation was to evaluate the stability of this antigen under refrigeration for use in the complement fixation test. Fourteen batches of antigen prepared with Brucella abortus strain 1119/3, produced from 9 months to 23 years and 11 months before, were analysed. One hundred and sixty-seven cattle sera with varying titres of antibodies to Brucella were tested through the warm complement fixation microtechnique with five 50% haemolytic units of complement. Sera with at least 25% of complement fixation in dilution 1:4 were considered positive. The results with 13 of the antigen batches were compared with the results obtained with the batch produced 9 months before by the McNemar c2 test and kappa statistic. The oldest antigen batch gave a higher proportion of sera titres which were exactly the same observed with the 9-month-batch (90.4%), and the antigen produced 4 years and 3 months before the test gave de lowest proportion of sera with the same titre of the 9-month-antigen (73.7%). The comparison of the results after being classified as positive and negative showed that the highest proportion of agreed results was observed with the antigen produced 21 years and 4 months before (98.8%, kappa 0.98). The antigen with the lowest proportion of agreed results was the one produced 3 years and 2 months before (91.6%, kappa 0.84). The results of the study show that most sera gave very similar results with all antigen batches evaluated, and that there was no relationship between the period of antigen production and the difference in test results.

Abstract in English:

ABSTRACT.- Monteiro L.A.R.C., Pellegrin A.O., Ishikawa M.M. & Osório A.L.A.R. 2006. [Epidemiological investigation of bovine brucellosis in an extract of Mato Grosso do Sul, Brazil.] Investigação epidemiológica da brucelose bovina em um estrato do Estado de Mato Grosso do Sul. Pesquisa Veterinária Brasileira 26(4):217-222. Programa Mestrado em Ciência Animal, Universidade Federal do Mato Grosso do Sul, Campo Grande, MS 79070-900, Brazil. E-mail: leticiacmonteiro@yahoo.com.br The study aimed to estimate the prevalence of bovine brucellosis in 22 counties which make up the region Extract 1 of the State of Mato Grosso do Sul, Brazil, in order to identify risk factors associated with the infection. The sample region encompasses an area of 70,214.1 km² and represents 19.7% of the State. The region studied has about 5.7 million head of cattle, corresponding to 23% of the total of 24.9 million cattle in the State of Mato Grosso do Sul. On 210 farms, between December 2003 and March 2004, 2,376 blood samples were collected from cows, aged 24 months or older, for serial diagnostic tests. Screening through the buffered acidified antigen test was confirmed by the 2-mercaptoetanol test. On the occasion of sample collection a questionnaire with information related to identification, kind of cattle and management practices was filled out. In individual animals the real prevalence was estimated at 5.6%, and in the cattle herds at 37.3%. The variables, which presented association through odds ratio (OR), univariate analysis and 95% confidence interval (CI) with serum positivity for brucellosis, were: the exploration of beef cattle (OR = 2.82, 95% CI = 1.49-5.34), Zebu breed (OR = 2.62, 95% CI = 1.40-4.88) and abortion (OR = 1.83, 95% CI = 1.01-3.33). The results shown here demonstrate, despite the prevalence of brucellosis in the extract of Mato Grosso do Sul studied, that the control of the disease may depend on adoption of a program focusing upon the exploration of beef cattle, the Zebu breed and the occurrence of abortion.

• Brucellosis cattle epidemiology seroprevalence

Abstract in Portuguese:

ABSTRACT.- Monteiro L.A.R.C., Pellegrin A.O., Ishikawa M.M. & Osório A.L.A.R. 2006. [Epidemiological investigation of bovine brucellosis in an extract of Mato Grosso do Sul, Brazil.] Investigação epidemiológica da brucelose bovina em um estrato do Estado de Mato Grosso do Sul. Pesquisa Veterinária Brasileira 26(4):217-222. Programa Mestrado em Ciência Animal, Universidade Federal do Mato Grosso do Sul, Campo Grande, MS 79070-900, Brazil. E-mail: leticiacmonteiro@yahoo.com.br The study aimed to estimate the prevalence of bovine brucellosis in 22 counties which make up the region Extract 1 of the State of Mato Grosso do Sul, Brazil, in order to identify risk factors associated with the infection. The sample region encompasses an area of 70,214.1 km² and represents 19.7% of the State. The region studied has about 5.7 million head of cattle, corresponding to 23% of the total of 24.9 million cattle in the State of Mato Grosso do Sul. On 210 farms, between December 2003 and March 2004, 2,376 blood samples were collected from cows, aged 24 months or older, for serial diagnostic tests. Screening through the buffered acidified antigen test was confirmed by the 2-mercaptoetanol test. On the occasion of sample collection a questionnaire with information related to identification, kind of cattle and management practices was filled out. In individual animals the real prevalence was estimated at 5.6%, and in the cattle herds at 37.3%. The variables, which presented association through odds ratio (OR), univariate analysis and 95% confidence interval (CI) with serum positivity for brucellosis, were: the exploration of beef cattle (OR = 2.82, 95% CI = 1.49-5.34), Zebu breed (OR = 2.62, 95% CI = 1.40-4.88) and abortion (OR = 1.83, 95% CI = 1.01-3.33). The results shown here demonstrate, despite the prevalence of brucellosis in the extract of Mato Grosso do Sul studied, that the control of the disease may depend on adoption of a program focusing upon the exploration of beef cattle, the Zebu breed and the occurrence of abortion.

Abstract in English:

ABSTRACT.- Jardim G.C., Pires P.P., Mathias L.A. & Ribeiro O.C. & Kuchembuck M.R.G. 2006. [Serological diagnosis of bovine brucellosis in adult herd vaccinated with Brucella abortus strain 19 reduced dose.] Diagnóstico sorológico da brucelose bovina em animais adultos vacinados com dose reduzida da cepa 19 de Brucella abortus. Pesquisa Veterinária Brasileira 26(3):177-182. Departamento de Medicina Veterinária, Universidade para o Desenvolvimento do Estado e Região do Pantanal (Uniderp), Rua Alexandre Herculano 1400, Parque dos Poderes, Campo Grande, MS 79037-280, Brazil. E-mail: gustavoj@mail.uniderp.br The study evaluated the use of a reduced dose of the Brucella abortus strain 19 vaccine, in an adult herd negative for the disease, by serological diagnostic techniques, advocated by the Brazilian Program for Animal Brucellosis and Tuberculosis Control and Eradication, and by an indirect ELISA. The complement fixation test detecteed 46.77% positives, the rose bengal test 67.74%, the mercaptoethanol with standard agglutination test 87.09% and the ELISA ID 100%. The reduced dose influenced the serological diagnosis. None of the techniques reached a suitable specificity for use in the herd under those conditions, up to 3 months after vaccination.

• Bovine brucellosis vaccination strain 19 serological diagnosis

Abstract in Portuguese:

ABSTRACT.- Jardim G.C., Pires P.P., Mathias L.A. & Ribeiro O.C. & Kuchembuck M.R.G. 2006. [Serological diagnosis of bovine brucellosis in adult herd vaccinated with Brucella abortus strain 19 reduced dose.] Diagnóstico sorológico da brucelose bovina em animais adultos vacinados com dose reduzida da cepa 19 de Brucella abortus. Pesquisa Veterinária Brasileira 26(3):177-182. Departamento de Medicina Veterinária, Universidade para o Desenvolvimento do Estado e Região do Pantanal (Uniderp), Rua Alexandre Herculano 1400, Parque dos Poderes, Campo Grande, MS 79037-280, Brazil. E-mail: gustavoj@mail.uniderp.br The study evaluated the use of a reduced dose of the Brucella abortus strain 19 vaccine, in an adult herd negative for the disease, by serological diagnostic techniques, advocated by the Brazilian Program for Animal Brucellosis and Tuberculosis Control and Eradication, and by an indirect ELISA. The complement fixation test detecteed 46.77% positives, the rose bengal test 67.74%, the mercaptoethanol with standard agglutination test 87.09% and the ELISA ID 100%. The reduced dose influenced the serological diagnosis. None of the techniques reached a suitable specificity for use in the herd under those conditions, up to 3 months after vaccination.

Abstract in English:

ABSTRACT.- Mathias, L.A., Chaves, L.F., Chen, A.A., Girio, R.J.S. & Valério Neto, W. 2001. [Evolution of serological antibody titres by the plate agglutination, rose Bengal and complement fixation tests in Nelore heifers (Bos indicus) vaccinated at 18 months of age with Brucella abortus strain 19] Evolução de títulos sorológicos, nas provas de soroaglutinação em placa, antígeno acidificado tamponado e fixação de complemento, em bezerras Nelore vacinadas aos 18 meses de idade com Brucella abortus amostra B 19. Pesquisa Veterinária Brasileira 21(4):139-142. Depto Medicina Veterinária Preventiva e Reprodução Animal, Faculdade de Ciências Agrárias e Veterinárias, Unesp-Campus de Jaboticabal, SP 14884-900, Brazil. One hundred and eight Nelore heifers (Bos indicus) about 18 months of age were vaccinated with a standard dosage (60-120 x 109 viable organisms) of Brucella abortus strain 19 vaccine, airning at to study the persistence of serological antibody titres by the plate agglutination, rase Bengal and cornplement fixation tests. Serum samples were collected just before vaccination and after 45 days, 6, 12 and 18 months. Before the vaccination, all the heifers showed negative results by the three tests. After 45 days, all the heifers had titres higher than or equal to 1/100 by the plate agglutination test and all of them showed positive results by the rose Bengal plate test, while 2 animals had titre 1/2 and 106 animals had titres higher than or equal to 1/4 by the complement fixation test. One year after the vaccination, most of the heifers did not show significant serological antibody titres. Considering the risk to which animals in endemic areas and infected herds are subjected, and considering the clear reduction of the serological antibody titres shown by most of the vaccinated heifers, one rnay assume that, in case of Nelore heifers in endemic areas and that were not vaccinated between 3 and 8 months of age, it would be more reasonable to vaccinate them at 18 months of age than to expose them to a high risk of Brucella infection.

• Bovine brucellosis strain 19 vaccine serological response Brucelose bovina vacina B 19 resposta sorológica.

Abstract in Portuguese:

RESUMO.- Mathias, L.A., Chaves, L.F., Chen, A.A., Girio, R.J.S. & Valério Neto, W. 2001. [Evolution of serological antibody titres by the plate agglutination, rose Bengal and complement fixation tests in Nelore heifers (Bos indicus) vaccinated at 18 months of age with Brucella abortus strain 19] Evolução de títulos sorológicos, nas provas de soroaglutinação em placa, antígeno acidificado tamponado e fixação de complemento, em bezerras Nelore vacinadas aos 18 meses de idade com Brucella abortus amostra B 19. Pesquisa Veterinária Brasileira 21(4):139-142. Depto Medicina Veterinária Preventiva e Reprodução Animal, Faculdade de Ciências Agrárias e Veterinárias, Unesp-Campus de Jaboticabal, SP 14884-900, Brazil. Com o objetivo de estudar a persistência da resposta sorológica, através das provas de soroaglutinação em placa, rosa Bengala e fixação de complemento, 108 bezerras, com idade ao redor de 18 meses, foram vacinadas com uma dose padrão da vacina preparada com Bntcella abortus amostra B 19. Foram obtidas amostras de soro sangüíneo antes da vacinação e após 45 dias, 6, 12 e 18 meses. Antes da vacinação, todas as bezerras apresentaram resultados negativos nos três testes. Após 45 dias, todas apresentaram título a partir de 1/100 na prova de soroaglutinação em placa e todas apresentaram resultado positivo no teste rosa Bengala, ao passo que dois animais apresentaram título 1/2 e os demais apresentaram título a partir de 1/4 na reação de fixação de complemento. Após um ano de vacinação, a grande maioria das bezerras já não apresentava título sorológico significativo. Considerando o risco a que estão sujeitos animais que vivem em áreas endêmicas e em propriedades onde a doença ocorre, e considerando a acentuada redução de título sorológico observada na grande maioria dos animais, pode-se concluir que, no caso bezerras de raças zebuínas em áreas endêmicas e que não tenham sido vacinadas na idade regulamentar, é mais vantajoso vaciná-las com a amostra B 19 aos 18 meses de idade do que deixá-las expostas a um elevado risco de infecção por Brucella.

Abstract in English:

The purpose of this study was to evaluate the competitive enzyme immunoassay used for the serological diagnosis of bovine brucellosis, comparing the results obtained using a conjugate prepared with monoclonal antibody and a conjugate prepared with policlonal sera. The results were also compareci with those obtained by a microtechnique of complement fixation. Two hundred and seventy-three sera from herds with a history of brucellosis, 205 sera from herds free of brucellosis and without vaccination with Brucella abortus strain 19 and 122 sera from herds without history of infection or vaccination were tested. Among sera from infected herds, the complement fixation test revealed antibody titres in 28.51%, the enzyme immunoassay using monoclonal conjugate in 39.19% and the enzyme immunoassay using policlonal conjugate revealed antibody titres in 37.0% of the sera. The agreement between complement fixation and the enzyme immunoassay using policlonal conjugate was 94.38% and the agreement between both of the enzyme immunoassays was 97.89%. Among the sera from vaccinated herds, the agreement between the complement fixation test and the enzyme immunoassay using policlonal conjugate was 69.39%, and the agreement between the enzyme immunoassays was 90.73%. The complement fixation test did not reveal any antibody titre in 67.86% of the sera from vaccinated herds, the enzyme immunoassay using policlonal conjugate did not reveal titres in 51.22% and the enzyme immunoassay with monoclonal conjugate did not reveal antibody titres in 41.95% of the sera from vaccinated herds. All the 122 sera from herds without infection or vaccination were negative to the three serological tests.

• Bovine brucellosis serological diagnosis competitive enzyme immunoassay

Abstract in Portuguese:

O objetivo do trabalho foi avaliar o comportamento do teste imunoenzimático competitivo quando aplicado ao diagnóstico sorológico da brucelose bovina, comparando-se o desempenho do teste ao usar um conjugado preparado com anticorpos monoclonais e um conjugado preparado com soro policlonal. Os resultados foram também comparados com aqueles obtidos através de uma microtécnica de fixação de complemento. Foram examinados 273 soros provenientes de rebanhos com histórico de brucelose, 205 soros provenientes de rebanhos sem problemas de infecção e que adotam a vacinação das bezerras com Brucella abortus amostra B 19 e 122 soros de bovinos procedentes de rebanhos sem histórico de brucelose e que não adotam a vacinação. Nos soros de rebanhos com histórico de infecção, a reação de fixação de complemento revelou títulos de anticorpos em 28, 51%, o teste imunoenzimático com o conjugado monoclonal revelou títulos em 39,19% e o teste imunoenzimático com o conjugado policlonal revelou títulos em 37,0% dos soros examinados, observando-se uma concordância de 94,38% entre a fixação de complemento e o teste imunoenzimático usando o conjugado policlonal e de 97,89% entre os dois testes imunoenzimáticos. Nos soros de rebanhos vacinados, a concordância entre a fixação de complemento e o teste imunoenzimático com o conjugado policlonal foi de 69,39%, enquanto que a concordância entre os testes imunoenzimáticos foi de 90,73%. Neste caso, a reação de fixação de complemento não revelou qualquer título em 67,86% dos soros examinados, o teste com o conjugado policlonal não revelou títulos em 51,22% dos soros, ao passo que o teste com o conjugado monoclonal não revelou título em 41,95% dos soros. Os 122 soros de rebanhos sem histórico de infecção e vacinação apresentaram resultados negativos nos três testes realizados.

• Brucelose bovina diagnóstico sorológico teste imunoenzimático competitivo

Abstract in English:

A competitive enzyme immunoassay was evaluated using as conjugate monoclonal antibodies B M-38 and B M-40, prepared from mice immunized with Brucellea melitensis 16 M. The competitive enzyme immunoassay was compared with the complement fixation test and an indirect enzyme immunoassay, regarding their efficiency and differential capacity to diagnose brucellosis in cattle vaccinated with B. abortus strain 19. Four hundred and twenty-one sera of vaccinated female calves, obtained between 15 days and 6 months after vaccination, were examined. The competitive enzyme immunoassay using conjugate BM-38 revealed a greater number of positive results (44,18%) than the complement fixation test (35,98%) and the competitive enzyme immunoassay using conjugate BM-40 (29,69%). This last test allowed a higher degree of differentiation than the others, since it revealed a lower number of reactors.

• Bovine brucellosis serological diagnosis competitive enzyme immunoassay

Abstract in Portuguese:

Foi avaliado o teste imunoenzimático competitivo, usando como conjugado os anticorpos monoclonais BM-38 e BM-40, preparados a partir da imunização de camundongos com Brucella melitensis 16 M, em comparação com a reação de fixação de complemento e com o teste imunoenzimático indireto, para diferenciar anticorpos da infecção natural dos induzidos pela vacina B19. Foram testados 421 soros de bezerras vacinadas com B. abortus amostra B 19 e colhidos em intervalos de 15 dias a 6 meses após a vacinação. O teste competitivo usando o conjugado BM-38 apresentou menor capacidade de discriminação que o teste com o conjugado BM-40 (44,18% contra 29,69% de soros com títulos de anticorpos) e que a reação de fixação de complemento (44,18% contra 35,98%) e resultados próximos aos do teste imunoenzimático indireto (54,89% contra 56, 17%), enquanto que o teste competitivo usando o conjugado BM-40 apresentou maior capacidade de discriminação do que os outros testes estudados, uma vez que acusou um menor número de reagentes: 28,9% contra 37, 6% revelados pela reação de fixação de complemento, 29,69% contra 44,18% revelados pelo teste com o conjugado BM-38 e 43,15% contra 56,85% revelados pelo teste imunoenzimático indireto.

• Brucelose bovina diagnóstico sorológico teste imunoenzimático competitivo