Comparison of infection by Brucella spp. in free-ranging and captive wild animals from São Paulo State, Brazil

The aim of the current study was to evaluate the infection rate by Brucella spp. in wild and in captive animals. Serum samples from 121 animals (94 free-ranging and 27 captive) of different mammal species were evaluated. Sera were submitted to rose Bengal test (RBT) for screening and serum agglutination tests (SAT) and 2-mercaptoethanol test (2-ME) for confirmatory results. Nine animals (five free-ranging and four captive) tested positive in RBT, but negative in the confirmatory tests. Several domestic animal diseases that have control programs are not focused on wild reservoirs, such as brucellosis in Brazil. The study of new reservoirs in wildlife is essential to prevent emerging diseases.

Serological profile of buffalo (Bubalus bubalis) female calves vaccinated with standard Brucella abortus strain 19 vaccine using rose bengal, 2-mercaptoethanol and complement fixation tests

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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)

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.

Aglutininas anti-Brucella abortus no soro e em secreção de bursite cervical em eqüinos

Fistulous wither secretions from three horses were tested by the plate agglutination (PAT), tube agglutination (SAT), buffered plate-Rose Bengal (RBPT) and 2-mercaptoethanol (2-ME) tests, comparatively with standard agglutination tests. In the modified tests, titers were increased in the PAT, SAT and 2-ME tests and positive reaction was observed in RBPT. Brucella abortus was isolated from the secretion of fistulous withers collected from one animal. These results suggest that the modified tests may be used as alternative tests to diagnose brucellosis in horses with fistulous withers.

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.

Perfil sorológico, isolamento bacteriano e valores hematológicos e urinários em cães naturalmente infectados com Brucella canis

Descrevem-se os parâmetros hematológicos, urinários, perfil sorológico de aglutininas antibrucélicas e resultados de isolamento bacteriano de swab vaginal, líquido prostático e hemocultura de 12 cães naturalmente infectados por Brucella canis. Observaram-se flutuação dos resultados sorológicos, ausência de isolamento de B. canis nos diversos materiais colhidos e valores hematológicos e urinários predominantemente normais. Discute-se o diagnóstico de brucelose canina em nível individual.

Ocorrência de anticorpos anti-Brucella abortus e anti-Brucella canis em cães rurais e urbanos do Município de Monte Negro, Rondônia, Brasil

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

Perfil sorológico anti-Brucella abortus em bezerras vacinadas com amostras B19

The serological profiles of 33 female bovines, vaccinated at three to eight months of age with the B19 standard strain of Brucella abortus, were studied over a period of 728 days, using the following agglutination procedures: plate agglutination, tube agglutination, rose bengal plate and mercaptoethanol test. Maximum levels of antibodies detected reached by the plate agglutination and tube agglutination tests were found between the 14(th) and 42(nd) day, and with mercaptoethanol test, between the 28(th) and 42(nd) day. Anti-Brucella antibodies decreased thereafter. At 182 days after vaccination, five suspected animals and one positive were detected by the plate agglutination test, while by the tube agglutination test, only one animal was suspected and another one was positive. During the same period, positive reactions were found in six animals by means of the mercaptoethanol test, and five positives by the rose bengal test. By means of tube agglutination and plate agglutination tests, the animals became serologically negative at 245 and 273 days, respectively, after the vaccination, based on the rules adopted for the vaccinated animals. Using the mercaptoethanol and rose bengal plate tests, all the animals were found to be negative at 308 days after vaccination.

Pesquisa de anticorpos contra Brucella ovis em ovinos do Estado de São Paulo

Eight hundred and fifty sheep sera from 18 herds, located in 15 municipalities of the State of São Paulo, were examined by complement fixation test, indirect enzyme immunoassay and gel diffusion test for antibodies to Brucella ovis. The combination of the serological test results and the clinical and epidemiological data suggest that none of the examined animals was infected. The complement fixation and the gel diffusion tests showed good specificity, but the indirect enzyme immunoassay showed false positive results in nine of the sera.

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.

Rough virulent strain of Brucella ovis induces pro- and anti-inflammatory cytokines in reproductive tissues in experimentally infected rams

The ovine brucellosis caused by Brucella ovis has tropism for reproductive tissues but until now the mechanism of bacterial persistence is not understood. Cytokine expression profiles were studied for 8 months in rams after being experimentally infected with the rough virulent strain of B. ovis (R- B. ovis) to study the pathogenesis of B. ovis and immune mechanism possibly associated to bacteria tropism and persistence. The messenger RNA (mRNA) expression levels of interleukin-1α (IL-1α), IL-1β, IL-6, IL-10, IL-12, interferon-γ (INF-γ) and tumour necrosis factor-α (TNF-α) cytokines were quantified by real-time quantitative RT-PCR (qRT-PCR) in reproductive tissues (epididymus, testicles, ampolae, vesicular glands and bulbourethral glands), and non-reproductive (liver, spleen and kidneys) tissues at 30, 60, 120 and 240 days post infection (dpi). During the acute phase of infection at 30. dpi, the host immune response was most notable demonstrating an up-regulation of several cytokines in reproductive tissues, including the epididymus (IL-6, IL-1β and IL-1α), testicles (INF-γ and IL-12), bulbourethral glands (IL-6 and TNF-α) and ampolae (INF-γ, IL-10, IL-1β and IL-1α). During the development of infection, cytokine gene expression levels decreased, providing evidence of immunosuppression and evidence of immune evasion that favoured persistence of chronic R- B. ovis infection. During the chronic phase of R- B. ovis infection (120 and 240. dpi), cytokine production was down-regulated in the epididymus (IL-1β and IL-1α), testicles (INF-γ and IL-12), and ampolae (INF-γ, IL-10, IL-1β and IL-1α), with the exception of the bulbourethral glands (IL-6 and TNF-α) and epididymus (IL-6); in these tissues, R- B. ovis infection resulted in up-regulation of the pro-inflammatory cytokine IL-6. Herein, we report cytokine expression profiles in tissues of rams experimentally infected with the rough strain of B. ovis, which are associated with bacterial persistence and macrophage activation. © 2012 Elsevier B.V.

Brucella ovis REO 198 natural and experimental infection in Santa Inês rams from Brazil

B. ovis pathogenicity was evaluated in experimentally inoculated and naturally infected rams. Ten animals were submitted to simultaneous conjunctival and intrapreputial inoculation with 2x109 CFU/ mL of B. ovis REO 198. After that, animals underwent physical examination and blood samples were collected for serology every week. Positive serology results started to be observed in the 3rd week, with fluctuations in titers. Clinical changes began in the 5th week after inoculation and were associated with positive serology in the acute phase of the disease. Presence of B. ovis in semen and urine culture was intermittent. Three non-inoculated animals showed natural infection. B. ovis was shed twice in semen of one serology-negative animal. The study underscored the pathogenic characteristics of B. ovis REO 198 in Santa Inês rams, as well as the importance of animals as potential sources of infection.