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RESUMO:O objetivo deste trabalho foi analisar a frequência de lesões macroscópicas sugestivas de tuberculose em carcaças de bovinos reagentes ao teste intradérmico de tuberculose. Os animais do estudo foram provenientes de rebanhos de exploração leiteira, localizados nos municípios de Perdizes, Patos de Minas, Lagoa Formosa e Uberlândia, Minas Gerais. Foram avaliadas 140 carcaças de bovinos positivos no teste cervical comparativo. Durante o abate sanitário foi realizada inspeção post mortem das carcaças, e as lesões macroscópicas sugestivas de tuberculose foram registradas. Foram avaliados os linfonodos mediastínicos, fígado, pulmão e carcaça. Dos 140 bovinos examinados, 78 (55%) apresentaram algum tipo de lesão macroscópica sugestiva de tuberculose, 38 (49%) ocorreram exclusivamente nos linfonodos mediastínicos, 22 (28%) no fígado e 11 (14%) no pulmão; 5 (6%) carcaças apresentaram lesões no fígado, pulmão e linfonodo mediastínico, e 2 (4%) tiveram lesões no pulmão e linfonodo. Concluem-se que as lesões não visualizadas em bovinos reagentes ao teste tuberculínico podem ocorrer e estariam relacionadas principalmente ao estágio de evolução da doença, tempo insuficiente na inspeção post mortem para detecção, bem como reações inespecíficas para outras micobactérias. PALAVRAS-CHAVE: ABSTRACT:The aim of this study was to analyze the frequency of macroscopic lesions suggestive of tuberculosis in cattle reacting to the tuberculin test. Cattle of this study were from dairy herds located in the cities of Perdizes, Patos de Minas, Lagoa Formosa and Uberlândia, Minas Gerais, Brazil. We evaluated 140 cattle carcasses positive to the cervical comparative intradermal tuberculin test. During the slaughter a post-mortem inspection of carcasses was done, and the lesions suggestive of tuberculosis were recorded. We evaluated the mediastinal lymph nodes, liver, lung and carcass. Of the 140 cattle examined, 78 (55%) carcasses had some kind of macroscopic lesions suggestive of tuberculosis, 38 (49%) occurred only in the mediastinal lymph nodes, 22 (28%) in the liver and 11 (14%) in the lungs; 5 (6%) carcasses showed lesions in liver, lungs and lymph node, and 2 (4%) showed lesions in lung and lymph nodes. We concluded that lesions that were not visualized in bovine tuberculin skin test reagents may occur and are related mainly to the stage of the disease, insufficient time to detect the lesions, and nonspecific reactions to other mycobacteria.

Semen contaminated with microorganisms can disseminate serious diseases including brucellosis. The objectives of this study were to detect Brucella-specific antibodies and Brucella abortus DNA in samples of blood and fresh semen from 100 animals older than 20 months. The samples were collected on farms and in semen collection and processing centers (CCPS). The serum samples were evaluated by Rose Bengal test (RBT). B. abortus DNA was detected by a polymerase chain reaction (PCR) using BAB and IS771 primers. The difference between the vaccine field strain was identified using ery-1, ery-2, and ery-3 primers, using the hemi-nested PCR method. No anti-B. abortus antibodies were detected in the serum samples. Out of the total semen samples, 68% (68/100) presented amplifications of the B. abortus genes. All (68/68) were identified as B19 strain of Brucella abortus vaccine. It was concluded that even bulls that are seronegative for brucellosis can eliminate the bacteria in the semen. The presence in the DNA of the B19 vaccine strain should be investigated for a better understanding of the epidemiological importance of this strain in these animals.

Background: The immunoglobulin Y is a principal antibody current in the blood of hens, which are transferred from the maternal blood serum to the egg yolk. The extraction of IgY from the egg yolk apply animal welfare when compared to the extraction of IgG, reducing the number of animals and prevent a bleeding of hens through the extraction of the IgY from eggs, besides that IgY presenting high specificity for antigenic binding. The objective of this study was to produce specific polyclonal IgY antibodies anti-Brucella abortus by immunizing hens with B19 vaccine and evaluate their reactivity through Buffered Acidified Plate Antigen (BAPA), 2-Mercaptoethanol (2-ME) and indirect ELISA diagnostic tests.Materials, Methods & Results: Four 25-week-old White Leghorn hens were immunized, two of them comprising the control group (Group 1) with phosphate-buffered saline (PBS) with adjuvant, and the others two immunized with B19 vaccine (Brucella abortus vaccine strain B19), representing the Group 2. The immunizations occurred six times with a 15-day interval between each. Blood samples were taken biweekly (seven times); and daily, the eggs were collected for 13 weeks, the first collection of blood and eggs, performed one week before the first immunization of each group. The IgY was purified from egg yolk, using the method of dilution in acid water and precipitation with ammonium sulfate for delipidation. BAPA, 2-ME and ELISA tests performed to verify the specificity of IgY confirmed the reactivity of polyclonal antibodies specific to the antigen used both in blood serum samples and in the purified egg yolks. The hens from the control group did not present reactivity in the diagnostic tests used, which was already expected, since no antigen was used in any of their immunizations. Hens immunized with the Brucella abortus B19 vaccine produced detectable reactive antibodies in the three tests used on blood serum and IgY samples extracted from the egg yolk. In Group 2 (vaccine B19), blood serum samples started to react one week after the first inoculation, and the IgY samples extracted from the egg yolk were reagent two weeks after serum IgY appear reactivity, showing the transfer of specific antibodies to the egg yolk, was late.Discussion: Although the transfer of serum Igy to egg yolk was late when compared to others authors which found that the transovarian passage of immunoglobulin Y occurred in approximately three to six days after IgY being detected in blood serum, the results of this study showed the occurrence of the transfer of blood serum IgY anti-Brucella abortus to egg yolk of hens immunized with B19 vaccine, the same found by others researches found the same results with others antigens. Thus, it can be concluded that immunoglobulins Y produced in this study can be used as specific antibodies in diagnostic tests for the detection of the Brucella abortus antigen, in addition, this process guarantees the welfare of the animal, since it avoids bleeding and it is possible to obtain high concentrations of antibodies directly from the hen egg, which is a great advantage, because IgY can be easily isolated from the egg yolk by the precipitation technique discarding the need of invasive and painful procedures that involve bloody interventions to obtain the serum antibodies like occur in mammals for extraction of IgG.

A Brucelose e a Tuberculose bovina são zoonoses de distribuição mundial e encontram-se disseminadas por todo território nacional. A importância econômica atribuída a essas doenças está baseada nas perdas diretas resultantes da morte de animais, da queda no ganho de peso, diminuição da