Avian mycobacteriosis in chickens from a rural area of Argentina

An outbreak of avian tuberculosis was detected in chickens from a rural area of Chaco Province, northeastern Argentina. The hens were emaciated and presented granulomatous lesions of various sizes throughout the internal organs. The lesions observed in three necropsied birds consisted of granulomas containing alcohol/acid-fast bacilli. All the lesions found were diagnosed histopathologically as tuberculosis, Mycobacterium avium subsp. avium were isolated from the cultures and confirmed by polymerase chain reaction techniques

Primer aislamiento de Mycobacterium bovis de búfalo del nordeste argentino

Para detectar búfalos infectados con Mycobacterium bovis se realizaron pruebas tuberculínicas intradérmicas a 402 búfalos de raza Murrah del nordeste argentino. Cuatro animales resultaron positivos y seis sospechosos a la prueba ano–caudal simple, de los cuales cinco fueron positivos a la prueba cervical comparada. Se realizó necropsia a una hembra de 9 años que había reaccionado positivamente a ambas pruebas, en la que se observó sólo un ganglio retromamario afectado con necrosis caseosa. A partir del mismo se aisló M. bovis espoligotipo 34, que es el más frecuente en los aislamientos provenientes del ganado bovino de la zona. Se destaca la ubicación del linfonódulo afectado para tenerla en cuenta en las necropsias de la especie bubalina

Polymorphisms of 20 regulatory proteins between Mycobacterium tuberculosis and Mycobacterium bovis.

Mycobacterium tuberculosis and Mycobacterium bovis are responsible for tuberculosis in humans and animals, respectively. Both species are closely related and belong to the Mycobacterium tuberculosis complex (MTC). M. tuberculosis is the most ancient species from which M. bovis and other members of the MTCevolved. The genome of M. bovis is over>99.95% identical to that of M. tuberculosis but with seven deletions ranging in size from 1 to 12.7 kb. In addition, 1200 single nucleotide mutations in coding regions distinguish M. bovis from M. tuberculosis. In the present study, we assessed 75 M. tuberculosis genomes and 23 M. bovis genomes to identify non-synonymous mutations in 202 coding sequences of regulatory genes between both species. We identified species-specific variants in 20 regulatory proteins and confirmed differential expression of hypoxia-related genes between M. bovis and M. tuberculosis

Epidemiological Study of Mycobacterium bovis Infection in Buffalo and Cattle in Amazonas, Brazil.

Bovine Tuberculosis (BTB) is an endemic disease in about one hundred countries, affecting the economy causing a decrease in productivity, condemnation of meat, and damaging the credibility on international trade. Additionally, Mycobacterium bovis the major causative agent for BTB can also infect humans causing a variety of clinical presentations. The aim of this study was to determine BTB prevalence and the main risk factors for theMycobacterium bovis prevalence in cattle and buffalos in Amazonas State, Brazil. Tissue samples from 151 animals (45 buffalo and 106 cattle from five herds with buffalo only, 22 herds with cattle only, and 12 herds with buffalo and cattle) were obtained from slaughterhouses under State Veterinary Inspection. M. bovis were isolated on Stonebrink medium. The positive cultures were confirmed by polymerase chain reaction (PCR) testing. The apparent herd and animal prevalence rates were 56.4 and 5.40%, respectively. Regarding animal species, the apparent prevalence rates were 3% in cattle and 11.8% in buffalo. Generalized Linear Mixed Models (GLMM) with random effect were used to assess the association with risk factors on the prevalence. Species (buffalo), herds size (>100 animals) and the presence of both species (buffalo and cattle) in the herd were the major risk factors for the infection by Mycobacterium bovis in the region. The findings reveal an urgent need for evidence-based effective intervention to reduce BTB prevalence in cattle and buffalo and prevent its spread to the human population. Studies are needed to understand why buffalo are more likely to be infected by M. bovis than cattle in Amazon. Recommendations for zoning, use of data from the inspection services to generate information regarding BTB focus, adoption of epidemiological tools, and discouragement of practices that promote the mixing of cattle and buffalo, were made

First identification of Mycobacterium avium paratuberculosis sheep strain in Argentina

We here identified for the first time the presence of Mycobacterium avium paratuberculosis (MAP) sheep (S) strain in Argentina. IS900 polymerase chain reaction (PCR) was positive. The S strain was compared with MAP cattle (C) strains by using IS1311 PCR-restriction endonuclease analysis (PCR-REA), multiplex PCR and restriction fragment length polymorphism (RFLP) analysis.Fil: Traveria, Gabriel. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias. Departamento de Clinica. Centro de Diagnostico E Investigaciones Veterinarias; ArgentinaFil: Zumárraga, Martín José. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Etchechoury, Ignacio. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Romano, Maria Isabel. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cataldi, Angel Adrian. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alvarado Pinedo, M. F.. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias. Departamento de Clinica. Centro de Diagnostico E Investigaciones Veterinarias; ArgentinaFil: Pavlik, I.. Veterinary Research Institute; República ChecaFil: Pribylova, R.. Veterinary Research Institute; República ChecaFil: Romero, J. R.. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias. Departamento de Clinica. Centro de Diagnostico E Investigaciones Veterinarias; Argentin

Matrix Assisted Laser Desorption Ionization-Time-of-Flight mass spectrometry identification of Mycobacterium bovis in Bovinae.

In this study, Matrix Assisted Laser Desorption Ionization-Time-of-Flight (MALDITOF) mass spectrometry was used to identify Mycobacterium bovis from cattle and buffalo tissue isolates from the North and South regions of Brazil, grown in solid medium and previously identified by Polymerase Chain Reaction (PCR) based on Region of Difference 4 (RD4), sequencing and spoligotyping. For this purpose, the protein extraction protocol and the mass spectra reference database were optimized for the identification of 80 clinical isolates of mycobacteria. As a result of this optimization, it was possible to identify and differentiate M. bovis from other members of the Mycobacterium tuberculosis complex with 100% specificity, 90.91% sensitivity and 91.25% reliability. MALDI-TOF MS methodology described herein provides successful identification of M. bovis within bovine/bubaline clinical samples, demonstrating its usefulness for bovine tuberculosis diagnosis in the future

Analysing nonsynonymous mutations between two Mycobacterium bovis strains with contrasting pathogenic profiles.

Mycobacterium bovis (M. bovis) is the causative agent of bovine tuberculosis, a chronic infectious disease that can affect cattle, other domesticated species, wild animals and humans. This disease produces important economic losses worldwide. Two M. bovis strains (04-303 and 534) have been isolated in Argentina. Whereas the 04-303 strain was isolated from a wild boar, the 534 strain was obtained from cattle. In a previous study, six weeks after infection, the 04-303 strain induced 100% mortality in mice. By contrast, mice infected with the 534 strain survived, with limited tissue damage, after four months. In this study we compared all predictive proteins encoded in both M. bovis genomes. The comparative analysis revealed 141 polymorphic proteins between both strains. From these proteins, nine virulence proteins showed polymorphisms in 04-303, whereas five did it in the 534 strain. Remarkably, both strains contained a high level of polymorphism in proteins related to phthiocerol dimycocerosate (PDIM) synthesis or transport. Further experimental evidence indicated that only mutations in the 534 strain have an impact on PDIM synthesis. The observed reduction in PDIM content in the 534 strain, together with its low capacity to induce phagosome arrest, may be associated with the reported deficiency of this strain to replicate and survive inside bovine macrophages. The findings of this study could contribute to a better understanding of pathogenicity and virulence aspects of M. bovis, which is essential for further studies aiming at developing new vaccines and diagnostic techniques for bovines