Comparison of Brucella agar, CITA and Farrel media for selective isolation of Brucella abortus from semen of bovine bulls

Brucellosis remains as a public health concern worldwide. In domestic animals, the disease is characterized by reproductive disorders in male and female. Besides extensive use of serological tests and recent development of molecular biology techniques, microbiological culture of Brucella species is yet considered a “gold standard” method for diagnosis. Here, semen of 335 bovine bulls was subjected simultaneously to microbiological culture in Brucella agar, Farrell media, and CITA media to evaluate comparatively the best selective media for isolation of Brucella sp. Among all 335 samples, B. abortus B19 strain was isolated from semen of five (1.49%) bulls using the three selective media. However, Farrell media was considered the best selective media for microbiological diagnosis, because of allowed isolation of B. abortus B19 strain from bull semen without bacterial commensal or fungal contamination of plates.

Leptospira spp. e Brucella spp. em feitos e oócitos colhidos de vacas no momento do abate

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Pesquisa de Brucella spp. em linfonodos de suínos e javalis com linfadenite

Pós-graduação em Medicina Veterinária - FMVZ

Evaluation of Three Formulations of Culture Media for Isolation of Brucella spp. regarding Their Ability to Inhibit the Growth of Contaminating Organisms

Three culture media (Brucella agar, Farrell medium, and CITA) were compared for their effectiveness in inhibiting contamination and for isolating Brucella spp. One hundred lymph nodes from pigs (n = 50) and wild boars (n = 50) with lymphadenitis were collected in slaughterhouses in the State of Sao Paulo and were assessed on these three selective media for Brucella spp. All of the samples were negative for Brucella spp. on the three culture media. On the agar medium, fungal (70 plates) and Gram-positive bacterial (59 plates) contaminants were observed; in the CITA medium, the absence of fungal and Gram-positive bacteria on 15 plates was observed; no bacterial or fungal growth was observed on the Farrell media. The results demonstrated that the CITA and Farrell media inhibited the growth of contaminants better than the Brucella agar.

A comparison of two agar gel immunodiffusion methods and a complement fixation test for serologic diagnosis of Brucella ovis infection in experimentally infected rams

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Rapid serum agglutination and agar gel immunodiffusion tests associated to clinical signs in rams experimentally infected with Brucella ovis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Comparison of agar gel immunodiffusion test, rapid slide agglutination test, microbiological culture and PCR for the diagnosis of canine brucellosis

The performance of the rapid slide agglutination test, with and without 2-mercaptoethanol (RSAT and 2ME-RSAT) and agar gel immunodiffusion test (AGID) was evaluated for the diagnosis of brucellosis in naturally infected dogs. The microbiological culture, PCR and clinical parameters were used as reference. A total of 167 dogs were clinically examined and tested by blood culture, culture of semen/vaginal swab and PCR in blood and semen/vaginal swab. According to the results observed the 167 dogs were divided into three groups: Brucella canis infected dogs (Group 1). B. canis non-infected dogs (Group 2) and dogs with suspected brucellosis (Group 3). The dogs were then tested by RSAT, 2ME-RSAT and AGID. Groups 1 and 2 were used to calculate the diagnostic sensitivity and specificity of the serological tests and the results observed in Group 3 were also discussed. The diagnostic sensitivity of RSAT, 2ME-RSAT and AGID was respectively 70.58%, 31.76%, and 52.94%. The diagnostic specificity of RSAT, 2ME-RSAT and AGID was respectively 83.34%, 100%, and 100%. In dogs with suspected brucellosis 15% were RSAT positive, none was 2ME-RSAT positive and 5% were AGID positive. Although the serological tests are the most commonly used methods for brucellosis diagnosis, a significant proportion of false-negative results were observed highlighting the importance of the direct methods of diagnosis, like blood culture and PCR to improve the diagnosis of canine brucellosis. (c) 2008 Elsevier Ltd. All rights reserved.

Validation of an ELISA method for the serological diagnosis of canine brucellosis due to Brucella canis

In the present study, the validation of an enzyme-linked immunosorbent assay (ELISA) for serodiagnosis of canine brucellosis is described. Two different antigenic extracts, obtained by heat or ultrasonic homogenization of microbial antigens from a wild isolate of Brucella canis bacteria, were compared by ELISA and Western blot (WB). A total of 145 canine sera were used to define sensitivity, specificity and accuracy of the ELISA as follows: (1) sera from 34 animals with natural B. canis infection, confirmed by blood culture and PCR, as well as 51 sera samples from healthy dogs with negative results by the agar-gel immunodiffusion (ACID) test for canine brucellosis, were used as the control panel for B. cants infection; and (2) to scrutinize the possibility of cross reactions with other common dog infections in the same geographical area in Brazil, 60 sera samples from dogs harboring known infections by Leptospira sp., Ehrlichia canis, canine distemper virus (CDV), Neospora caninum, Babesia canis and Leishmania chagasi (10 in each group) were included in the study. The ELISA using heat soluble bacterial extract (HE-antigen) as antigen showed the best values of sensitivity (91.18%), specificity (100%) and accuracy (96.47%). In the WB analyses, the HE-antigen showed no cross-reactivity with sera from dogs with different infections, while the B. canis sonicate had various protein bands identified by those sera. The performance of the ELISA standardized with the heat soluble B. canis antigen indicates that this assay can be used as a reliable and practical method to confirm infection by this microorganism, as well as a tool for seroepidemiological studies. (C) 2010 Elsevier Ltd. All rights reserved.

Isolation of brucella spp from milk of brucellosis positive cows in São Paulo and Minas Gerais states

A brucelose é uma zoonose crônica de importância para a Saúde Pública. Considerando o pequeno número de dados brasileiros sobre a sua presença em leite cru e derivados não-pasteurizados, estudamos a presença de brucelas em leite de animais sorologicamente positivos. A soroaglutinação rápida (SAR), a soroaglutinação lenta (SAL) e a soroaglutinação lenta com tratamento do soro com 2-mercaptoetanol foram utilizados para identificar os animais positivos nas propriedades estudadas. Amostras diárias de 300 ml de leite foram colhidas por três dias de todos os quartos mamários produtivos (75 ml/teto). As amostras eram misturadas e centrifugadas. Parte do sedimento e do sobrenadante foi inoculada em meios de Farrel e Brodie-Sinton (BS) suplementados com agentes antimicrobianos. As placas e tubos foram cultivados por sete dias a 37ºC, em microaerofilia. As colônias suspeitas no meio BS foram imediatamente repicadas para ágar-Brucella, e cultivadas sob a mesma condição. Os microrganismos isolados foram submetidos a procedimentos de identificação, incluindo a coloração de Gram, requerimento de CO2, produção de H2S, atividade da urease e crescimento na presença de tionina e fucsina. Das 49 amostras examinadas, isolou-se Brucella abortus de 15 (30,61%). Os biótipos isolados foram: biótipo 1 em uma amostra (2,04%), biótipo 2 em oito (16,32%) e biótipo 3 em seis amostras (12,25%)

Comparison of agar gel immunodiffusion test, rapid slide agglutination test, microbiological culture and PCR for the diagnosis of canine brucellosis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Imunodifusão em gel de ágar com polissacarídeos de membrana de Brucella abortus 1119-3 no diagnóstico da brucelose bovina

Comparou-se a prova de imunodifusão em gel de ágar (IDGA), utilizando extrato polissacarídico (POLI O), obtido da amostra de B. abortus 1119-3, com os testes de soroaglutinação rápida em placa, de soroaglutinação lenta em tubos, de antígeno acidificado e de 2-mercaptoetanol para o diagnóstico da brucelose bovina. O IDGA mostrou alta especificidade, porém sensibilidade inferior aos métodos convencionais.

Infecção em cão por Brucella abortus: relato de caso

Brucella abortus infection is reported in a dog from a rural area that presented at clinical evaluation left testicular enlargement and right testicular decrease. Serum resulted negative to rapid agglutination test and agar gel immunodifusion with Brucella ovis antigen but positive to buffered plate agglutination test, tube agglutination test and 2- Mercapthoetanol with B. abortus antigen. Brucella isolation was negative in blood, testicular material, semen and urine. Brucella DNA was detected in PCR from urine and blood.

Brazil Anticorpos anti-Brucella canis e anti-Brucella abortus em caes de Araguaina, Tocantins

The aims of the present study were to determine the seroprevalence of infection by Brucella canis and Brucella abortus and to evaluate possible risk factors for infection in dogs from Araguaina, Tocantins, Brazil. Sera from 374 dogs, of the urban zones of the municipality, from both sexes, were submitted to the agar-gel immunodiffusion for Brucella canisantibodies and to rose Bengal test (AAT) and fluorescence polarization assay (FPA) for Brucella abortus-antibodies. From the 374 tested dogs, 21 reacted in the AAT, but no one was positive in the FPA. The seroprevalence of B. canis infection found in Araguaina, Tocantins, Brazil, was 44.53% (95% IC; 39.43 to 49.72). No association was found among seropositivity for B. canis and the risk factors studied. Thus, data from the present study showed that there was no infection by B. abortus among dogs in the sample and that infection by B. canis is widespread and at high prevalence in Araguaina, Tocantins, Brazil.

Aspectos epidemiológicos, clínicos e avaliação dos métodos diagnósticos nas fases de evolução da brucelose em ovinos inoculados experimentalmente com Brucella ovis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Risk factors and presence of antibodies to Brucella canis and smooth Brucella in dogs from the municipality of Araguaina, Tocantins, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)