Sessenta amostras de fragmentos de tecidos com lesões sugestivas de tuberculose provenientes de abatedouros bovinos, conservadas em solução saturada de borato de sódio, foram submetidas a quatro tratamentos: descontaminação através dos métodos NaOH 4% (Método Petroff), H2SO4 12% e HPC (Cloreto de hexadecilpiridínio) 1,5%, e solução salina (controle). O método HPC apresentou a menor proporção de contaminação (3%), em relação ao controle (88%, p<0,001), NaOH (33%, p<0,001) e H2SO4 (21,7%, p=0,002). Em relação ao sucesso no isolamento, o método HPC apresentou o melhor resultado (40%), em relação ao controle (3%, p<0,001), NaOH (13%, p=0,001) e H2SO4 (1,7%, p<0,001). Os resultados indicam que o HPC é uma alternativa à utilização do método Petroff.

Sixty samples of tissue fragments with lesions suggestive of tuberculosis from bovine abattoirs, kept in saturated solution of sodium borate, were subjected to four treatments: 4% NaOH (Petroff Method), 12 % H2SO4 and 1.5% HPC (1-Hexadecylpyridinium Chloride) decontamination, and physiological saline solution (control). The HPC method showed the lowest contamination rate (3%) when compared to control (88%, p<0.001), NaOH (33%, p<0.001) and H2SO4 (21.7%, p<0.002). Regarding the isolation success, the HPC method was better (40%) than the control (3%, p<0.001), NaOH (13%, p=0.001) and H2SO4 (1.7%, p<0.001) methods. These results indicate that HPC is an alternative to the Petroff method.

As micobacterioses suínas são responsáveis por condenações de carcaças em abatedouro e uma das melhores formas de se conhecer os agentes envolvidos nos animais vivos é o isolamento a partir das fezes, pois em 94% das vezes, as lesões localizam-se no trato digestivo. Assim sendo, o presente estudo teve por objetivo comparar o desempenho de quatro métodos de descontaminação com semeadura em três diferentes meios de cultura, totalizando doze procedimentos na pesquisa de micobactérias a partir de amostras de fezes de suínos contaminadas experimentalmente. Amostras de fezes de suínos foram contaminadas artificialmente com 0,02g de Mycobacterium avium, estirpe de PIG-B, e submetidas à tentativa de isolamento de micobactérias, utilizando-se os seguintes protocolos de descontaminação: 1) Petroff modificado ou método básico; 2) Lowenstein-Jensen modificado ou método ácido; 3) Petroff modificado ou método básico e ressuspensão com anfotericina B; 4) Lowenstein-Jensen modificado ou método ácido e ressuspensão com anfotericina B; com subseqüente semeadura em meios de Petragnani, Lowenstein-Jensen e Lowenstein-Jensen com antibióticos (Penicilina G e Ácido nalidíxico). Houve diferença entre os percentuais de recuperação de micobactérias a partir das fezes de suínos (p<0,05) e o método ácido com ressuspensão em solução de anfotericina B e semeadura em meio de Lowenstein-Jensen com antibióticos apresentou os melhores resultados (87% de recuperação de micobactérias).

Swine mycobacteriosis is an important cause of carcass condemnation at abattoirs. One of the best ways to recognize the etiologic agent involved, in live animals, is the fecal isolation, as 94% of the lesions are located in the digestive tract. Therefore, the goal of the present study was to compare the performance of four decontamination methods followed by inoculation in three different culture media, totalizing twelve procedures of mycobacteria search from swine fecal samples experimentally contaminated. The swine feces were artificially contaminated with 0.02 g of Mycobacterium avium, PIG-B strain, and subjected to mycobacteria isolation trial. The protocols used were: 1) modified Petroff or basic method; 2) modified Lowenstein-Jensen or acidic method; 3) modified Petroff or basic method with re-suspension in Amphotericin B; 4) modified Lowenstein-Jensen or acid method with re-suspension in Amphotericin B, followed by inoculation in Petragnani, Lowenstein-Jensen and Lowenstein-Jensen medium with antibiotics (Penicillin G and Nalidixic acid). There was a difference (p<0.05) between the mycobacterial recovery percentages from swine feces. The acid method with re-suspension in Amphotericin B solution and inoculation in Lowenstein-Jensen medium with antibiotics showed the best results (87% of mycobacteria recovery).

Three leptospiral bacterins, produced with different serovars of Serogroup Sejroe, namely the hardjo (bacterin A), wolffi (bacterin B) and guaricura (bacterin C), were evaluated in male hamsters (Mesocricetus auratus) by comparing the agglutinating and neutralizing antibodies titers using microscopic agglutination (MAT) and in vitro growth inhibition (GIT) tests. The immunization schedule was based on two 1.0 mL doses of non-diluted formalininactivated whole culture bacterin given through subcutaneous route with 10-day interval. The challenge was performed ten days after the second vaccine dose, when the animals were inoculated with 0.2 mL of non-inactivated cultures of each serovar through intraperitoneal route. On the 21st post-challenge day (PCD), all animals were bled and their sera were joined in pools (n=8) and tested by MAT and GIT. All vaccinated and control animals presented no clinical signs of leptospirosis after the challenge, but the serovar guaricura was isolated from the kidneys of control animals on the 21st PCD. The MAT results showed cross agglutinins between serovars hardjo and wolffi, and between wolffi and guaricura. The GIT results revealed the presence of cross neutralizing antibodies between serovars wolffi or guaricura against hardjo, wolffi and guaricura. It was found that the tested strain of serovar hardjo did not produce detectable levels of neutralizing antibodies, indicating its poor immunogenicity.

Tendo sido comprovada a existência de quatro famílias molecularmente distintas de M. avium (PIG-A, B, C e D) circulando em suínos da região sul do Brasil, e havendo dúvidas a respeito da importância da transmissão horizontal como mecanismo de manutenção da doença, o presente teve por objetivo estudar a virulência dessas estirpes, informação importante para o aperfeiçoamento dos métodos de controle. Uma estirpe representante de cada família foi inoculada pela via intra-peritoneal em 48 hamsters com uma dose de 30.000 U.F.C. por animal. Após 2, 13, 26 e 40 dias da inoculação (T1 a T4), 12 hamsters inoculados de cada família foram anestesiados, sacrificados e os agentes foram quantificados no fígado, baço e pulmão. Os resultados foram expressos em número de U.F.C./g de órgão. A presença das estirpes foi pesquisada no sangue e também foram realizados exames histológicos. As estirpes PIG-A, B, C e D induziram a formação de lesões granulomatosas no fígado e baço a partir do segundo dia pós-inoculação e disseminaram-se pela via hemática, alcançando os pulmões. O baço sempre apresentou maiores contagens de U.F.C., seguido pelo figado e pulmões. Diferenças entre as estirpes foram constatadas através de análises das contagens de U.F.C de baço (T1: p<0,001; T2: p<0,001; T3: p<0,001 e T4: p<0,001), permitindo a construção da seguinte escala de virulência: PIG-B> PIG-A> PIG-D> PIG-C.

The finding of four clusters of M. avium (PIG-A, B, C and D), typed by the IS1245-RFLP method, infecting the swine population of the south region of Brazil, the possible existence of virulence differences among them, the role of the virulence in the transmission mechanisms of infections and the existence of reasonable doubts regarding the importance of horizontal transmission for swine micobacteriosis, the virulence of these four strains of M. avium were compared. Bacteria from each cluster were inoculated in 48 hamsters by intra-peritoneal route. On the 2nd, 13th, 26th, and 40th days after inoculation, (T1 to T4), 12 animals of each cluster were sacrificed with vapors of ethyl ether and the bacteria were quantified in the liver, spleen and lung. Results were expressed as cfu/g of organ. The presence of the strains was verified in the blood and histological exams were also accomplished. The four strains induced granulomatous lesions in the liver and spleen since 2 days after inoculation and were disseminated to the lungs through the blood stream. The cfu counts from spleen were always bigger them that obtained from liver and lungs. Differences among strains were observed through the analysis of cfu counts from spleen (T1: p<0,001; T2: p<0,001; T3: p<0,001 and T4: p<0,001), allowing the construction of the following virulence scale: PIG-B> PIG-A> PIG-D> PIG-C.