O carbúnculo sintomático é causado pelo Clostridium chauvoei, enquanto o edema maligno é causado pelo C. chauvoei, C. septicum, C. sordellii, C. perfringens tipo A, e/ou C. novyi tipo A. Corpos policlonais anti-C. chauvoei, anti-C. septicum, anti-C. sordellii and anti-C.novyi tipo A foram produzidos em coelhos e purificados em uma coluna de DEAE-celulose. Alíquotas das imunoglobulinas foram conjugadas com isotiocianato de fluoresceína e o restante foi usado na técnica de streptavidina biotina peroxidase (SBP). SBP foi padronizada para detectar C. chauvoei, C. septicum, C. sordellii e C. novyi tipo A em tecidos de cobaias fixados em formol e incluídos em parafina. A mesma foi comparada com a técnica de imunofluorescência direta (IFD). Secções e impressões do músculo da área de inoculação, coração, fígado, baço e rim, foram obtidas para ambas as técnicas. Nenhuma reação cruzada foi observada quando tecidos inoculados com outras espécies de Clostridia foram tratadas com esses quatro anticorpos primários. C. chauvoei e C. septicum foram detectados em todos os espécimes provenientes dos animais inoculados com esses microrganismos, enquanto somente secções de músculo obtidas de todos os animais inoculados com C. sordellii e C. novyi tipo A foram positivas. Os mesmos resultados observados pela técnica de SBP, foram obtidos em impressões de tecidos desses microrganismos corados pela IFD. Os resultados indicam que a técnica de SBP permite a detecção de C. chauvoei, C. septicum, C. sordellii e C. novyi tipo A em tecidos de cobaias fixados em formol e incluídos em parafina.

Blackleg is caused by Clostridium chauvoei, whereas malignant oedema is caused by C. chauvoei, C. septicum, C. sordellii, C. perfringens type A, and/or C. novyi type A. Anti-C. chauvoei, anti-C. septicum, anti-C. sordellii and anti-C. novyi type A polyclonal antibodies were produced in rabbits and purified in a column of DEAE-cellulose. Aliquots of the antisera were conjugated with fluorescein isothiocyanate and the remaining was used for the streptavidin biotin peroxidase technique (SBPT). SBPT was standardized to detect C. chauvoei, C. septicum, C. sordellii and C. novyi type A in formalin-fixed, paraffin-embedded tissues of guinea pigs. SBPT was compared to a fluorescent antibody technique (FAT). Sections and smears of muscle from inoculation area (MIA), heart, liver, spleen and kidney, were obtained for both SBPT and FAT. Cross-reactions between the different Clostridial species were not observed. C. chauvoei and C. septicum were detected in all specimens from the animals inoculated with these microorganisms, while only sections of muscle obtained from all the animals inoculated with C. sordellii and C. novyi type A were positive. The same results observed by the SBPT, were obtained on tissue smears of these microorganisms stained by the FAT. The results indicate that SBPT is suitable for detection of C. chauvoei, C. septicum, C. sordellii and C. novyi type A in formalin-fixed, paraffin-embedded tissues of guinea pigs.

Transmission of Mycobacterium bovis from cattle to humans has been reported and can cause tuberculosis (Tb) and a problem in certain risk populations. Therefore, knowledge of resistance of M. bovis towards antibiotics used for therapy of human Tb could help avoiding cure delay and treatment cost increase when dealing with drug resistant organisms. We therefore evaluated the susceptibility of M. bovis isolates towards streptomycin, isoniazide, rifampicin, ethambutol, and ethionamide, the first line antibiotics for human Tb. Therefore, 185 clinical samples from cattle with clinical signs of tuberculosis were processed and submitted to culturing and bacterial isolates to identification and drug susceptibility testing using the proportion method. Among 89 mycobacterial strains, 65 were identified as M. bovis and none were resistant to any of the antibiotics used. Confirmation of present results by future studies, enrolling a large number of isolates and designed to properly represent Brazilian regions, may favor the idea of using isoniazide preventive therapy as part of a Tb control strategy in special situations. Also, nucleic acids from bacterial isolates were submitted to rifoligotyping, a recently described reverse hybridization assay for detection of mutations causing resistance towards rifampicin. Concordance between the conventional and the molecular test was 100%, demonstrating the use of such methodology for rapid evaluation of drug susceptibility in M. bovis.