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Bovine brucellosis poses a risk to human health and causes serious economic losses for the animal industry. This report describes the use of different diagnostic methods for the diagnosis of brucellosis in cattle affected by cervical bursitis from a slaughterhouse located in São Luís, Maranhão, Brazil. Serum samples from a total of 47 cattle with bursitis were collected and submitted to the Rose Bengal Test (RBT), and RBT-positive samples were further confirmed by the 2-mercaptoethanol (2-ME) assay. RBT indicated 85.1% (40/47) of positive samples, from which 78.7% (37/47) were confirmed by 2-ME. Immunohistochemistry detected Brucella spp. in 34.0% (16/47) of tissues with bursitis. PCR and/or bacterial isolation demonstrated that 63.8% (30/47) of samples were positive and morphologically compatible with Brucella sp. All colonies suggestive of Brucella sp. were confirmed by PCR. Isolates were further characterized by PCR Multiplex AMOS-ENHANCED, which indicated that the isolates corresponded to biovar 1, 2, 4 (43.33%). This study evidences an association between cervical bursitis and Brucella spp. infection in cattle, and that different biovars of Brucella circulate in bovine herds in Maranhão.

A total of 27 seminal plasma samples from cattle-breeding farms or semen centres located in Minas Gerais, Brazil, previously negative by serological and tested positive for Brucella spp. with primer specific for the amplification of the gene virb5 by polymerase chain reaction (PCR) were analysed for the detection of Brucella abortus DNA by PCR. It was found that nine samples (33.33%) contained B. abortus B19 strain DNA, two (7.40%) contained B. abortus DNA and five (18.51%) contained both DNA. The larger number of samples with B. abortus B19 strain DNA would explained by the environmental contamination by vaccinated females with persistent excretion or some illegal vaccination process. It is first reported of male bovines detected with both DNA., (© 2017 Blackwell Verlag GmbH.)

Bovine brucellosis is an important zoonosis caused by Brucella abortus that negatively impacts livestock productivity. In 2001, Brazil launched a new national program aimed at eradicating animal brucellosis that included large-scale studies of the prevalence and risk factors to support strategic decision-making. These studies were implemented by the animal health authorities and were underpinned by the scientific coordination of the University of São Paulo and the University of Brasília. The state-level results were published and revealed important differences in herd prevalence among regions. The risk factors varied across states and did not clearly explain the observed spatial disease spread. This study used a consolidated herd-level database of 14 states and 17,100 herds, from the prevalence surveys' data, to gain insights into herd profiles and cattle production practices that might be associated with the risk of brucellosis. At the time of data collection, the study area comprised just over 56 million bovine females aged over 24 months and approximately 1.8 million herds. After an exploratory univariable analysis, all factors with p≤0.20 were included in a multiple logistic regression model, using the design-based method in order to take herd sampling weights into account. The number of females in the herd markedly increased the risk of infection; compared with smaller herds (less than 30 females), the odds ratio was 3.42 [CI 95% 2.98-3.91] for herds with 31 to 100 females, 5.68 [4.92-6.55] for herds with 101 to 400 females, and 13.14 [10.94-15.78] for herds with more than 400 females. The risk was higher for extensive cattle production farms (OR=1.23 [1.07-1.42]) and for farms that purchased replacement stock from cattle traders (OR=1.27 [1.08-1.47]) or directly from other farms (OR=1.19 [1.07-1.32]). The exclusive use of artificial insemination (OR=0.57 [0.4-0.81]) and regular veterinary support (OR=0.68 [0.6-0.77]) appeared to be protective factors. These findings are consistent with the regional prevalence trends observed in the study and provide key guidance for the planning of the national effort to control and eradicate brucellosis. High vaccination coverage of heifers is recommended, especially when targeted to areas where large-scale extensive cattle production predominates. The smaller, more intensive herds, are good candidates for disease accreditation schemes., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Between 2007 and 2009, a cross-sectional survey was carried out in Maranhão State, Brazil to estimate the seroprevalence of and risk factors for bovine brucellosis. In total, 749 herds and 6779 cows greater than two years of age were blood sampled. At the time of sampling a questionnaire to collect details on possible risk factors for bovine brucellosis was administered to the participating herd manager. A logistic regression model was developed to quantify the association between herd demographic and management characteristics and the herd-level brucellosis status. Spatial analyses were carried out to identify areas of the state where the presence of brucellosis was unaccounted-for by the explanatory variables in the logistic regression model. The estimated herd-level prevalence of brucellosis in Maranhão was 11.4% (95% CI 9.2-14) and the individual animal-level prevalence was 2.5% (95% CI 1.7-3.6). Herds with more than 54 cows older than two years of age, herds that used rented pasture to feed cattle, and the presence of wetlands on the home farm increased the risk of a herd being brucellosis positive. Infected farms were identified throughout the state, particularly in the central region and on the northwestern border. Spatial analyses of the Pearson residuals from the logistic regression model identified an area in the center of the state where brucellosis risk was not well explained by the predictors included in the final logistic regression model. Targeted investigations should be carried out in this area to determine more precisely the reasons for the unexplained disease excess. This process might uncover previously unrecognized risk factors for brucellosis in Maranhão., (Copyright © 2012 Elsevier B.V. All rights reserved.)