Detection of Mycobacterium avium subsp. paratuberculosis and other mycobacteria in retail milk and dairy products in Argentina

Mycobacterium avium subsp. paratuberculosis (MAP) is the etiologic agent of paratuberculosis or Johne’s disease (JD), a chronic enteritis disease that affects cattle and other animal species and has been linked to Crohn’s disease, a chronic inflammatory bowel disease in humans. MAP could resist pasteurization conditions and has been isolated from retail milk in several countries. The aims were to identify MAP and other mycobacteria in retail milk and dairy products in Argentina and to assess the product quality through Mesophilic Total Aerobic Bacteria (TAB) count. Three hundred and eighty-four samples of retail milk were tested for 24 months. All samples were negative for mycobacteria growth. However, 1.56% of the samples were positive for MAP identification by IS900-PCR. The TAB count was higher than the limits established by the Alimentary Argentinian Code (AAC) in 4.95% of the samples. Mycobacteria other than MAP were not detected either by culture or PCR. The MAP positive PCR from retail milk samples would indicate that they could come from dairy farms with JD and suggests that pasteurized milk or dairy products are not significant sources of human exposure to MAP in Argentina. Some milk samples exceeded the limits established by the AAC for TAB counts, indicating that commercialized milk could be processed and stored incorrectly.Mycobacterium avium subesp. paratuberculosis (MAP) es el agente etiológico de la paratuberculosis o la enfermedad de Johne (JD), una enteritis crónica que afecta al ganado vacuno y otras especies animales que se la vincula con la enfermedad de Crohn, una afección intestinal inflamatoria crónica en humanos. MAP podría resistir las condiciones de pasteurización y se lo aisló de la leche al por menor en varios países. Los objetivos fueron identificar MAP y otras micobacterias en leche y productos lácteos al por menor en Argentina y evaluar la calidad de estos a través del conteo de bacterias aerobias totales mesófilas (TAB). Se analizaron 384 muestras de leche de venta minorista durante 24 meses. Todas las muestras resultaron negativas en cuanto al crecimiento de micobacterias. Sin embargo, el 1.56% de las muestras dieron positivas en la identificación de MAP por IS900-PCR. El recuento de TAB superó los límites establecidos por el Código Alimentario Argentino (CAA) en el 4.95% de las muestras. No se detectaron micobacterias distintas de MAP ni por cultivo ni por PCR. La PCR positiva en MAP resultante de muestras de leche al por menor indicaría que podrían provenir de granjas lecheras con JD y sugiere que la leche pasteurizada o los productos lácteos no son fuentes significativas de exposición humana a MAP en Argentina. Algunas muestras de leche excedieron los límites establecidos por la AAC para los recuentos de TAB, lo cual indica que la leche comercializada podría procesarse y almacenarse incorrectamente.EEA BalcarceFil: Cirone, Karina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina.Fil: Cirone, Karina Mariela. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Morsella, Claudia Graciela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina.Fil: Mendez, Laura Luján. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Paolicchi, Fernando. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina.Fil: Paolicchi, Fernando. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina

Evidência de infecção intra-uterina por Mycobacterium avium subsp. paratuberculosis usando Multiple-Locus Variable-number tandem-repeat Analysis:: primeiro relato na Argentina

Uma novilha prenha em estado clínico avançado de paratuberculose foi observada em um rebanho bovino na Argentina. O animal foi eutanasiado e foram colhidas amostras dos seus órgãos e dos órgãos feto as quais foram cultivadas para bacteriologia em meio específico. Os tecidos foram examinados por histopatologia (coloração de hematoxilina-eosina e Ziehl-Neelsen). Na histopatologia das amostras colhidas da novilha foram observadas lesões compatíveis com paratuberculose e a coloração de Ziehl-Neelsen revelou a presença de bacilos álcool-ácido resistentes, nos tecidos fetais não foram observadas lesões, porém a coloração de Ziehl-Neelsen revelou a presença de bacilos álcool-ácido resistentes. Após o crescimento em meio específico, as colônias foram positivas para o teste IS900-PCR nos tecidos de ambos, vaca e feto, confirmando a presença de Mycobacterium avium subsp. paratuberculosis. Por fim, os isolados foram tipados por Multiple-Locus Variable-number tandem-repeat Analysis, confirmando a relação epidemiológicaentre eles. Este estudo relata a primeira detecção de Mycobacterium avium subsp. paratuberculosis na Argentina em que houve o compartilhamento de um tipo idêntico de MLVA em uma vaca prenhe e no seu feto. Os resultados deste estudo são consistentes com relatos anteriores e destacam a transmissão intra-uterina de Mycobacterium avium subsp. paratuberculosis como importante fonte de infecção nos rebanhos de bovinos.A pregnant heifer with an advanced clinical stage of paratuberculosis was reported in a herd in Argentina. Thus, the animal was euthanized and samples of organs of the cow and its fetus was taken and cultured for bacteriology in specific medium. Tissues were analyzed by histopathology (hematoxylin-eosin and Ziehl-Neelsen staining). Histopathological analysis of the cow’s samples revealed the presence of lesions consistent with paratuberculosis, and Ziehl-Neelsen staining revealed the presence of acid-fast bacilli, whereas the fetal tissues showed absence of lesions but the presence of acid-fast bacilli by Ziehl-Neelsen staining. After growing in specific medium, colonies in tissues from both cow and fetus were positive for IS900-PCR, confirming the presence of Mycobacterium avium subsp. paratuberculosis (MAP). Finally, the isolates were typed by Multiple-Locus Variable-number tandem-repeat Analysis (MLVA), which confirmedthe epidemiological link between them. This study is the first in Argentina to report the detection of MAP that shares an identical MLVA type in a pregnant cow and its fetus. The results of this study are consistent with previous reports and highlight the intra-uterine transmission of MAP as an important source of infection within herds

L-cysteine transporter-PCR to detect hydrogen sulfide-producing Campylobacter fetus

Phenotypic differences between Campylobacter fetus fetus and C. fetus venerealis subspecies allow the differential diagnosis of bovine genital campylobacteriosis. The hydrogensulfide production,for example,is atrait exclusive toC.fetus fetus and C. fetus venerealis biovar intermedius. This gas that can be biochemically tested can be produced from L-cysteine (L-Cys). Herein, we report a novel multiplex-PCR to differentiate C. fetus based on the evaluation of a deletion of an ATP-binding cassette-type L-Cys transporter that could be involved in hydrogen sulfide production, as previously described. A wet lab approach combined with an in silico whole genome data analysis showed complete agreement between this L-Cys transporter-PCR and the hydrogen sulfide production biochemical test. This multiplex-PCR may complement the tests currently employed for the differential diagnosis of C. fetus.Instituto de BiotecnologíaFil: Farace, Pablo Daniel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET); ArgentinaFil: Morsella, Claudia Graciela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Laboratorio de Bacteriología-Grupo de Sanidad Animal. Universidad Nacional de Mar del Plata; ArgentinaFil: Cravero, Silvio Lorenzo Pedro. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET); ArgentinaFil: Sioya, Bernardo Arturo. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET); ArgentinaFil: Amadio, Ariel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela; Argentina. Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET); ArgentinaFil: Paolicchi, Fernando. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Laboratorio de Bacteriología-Grupo de Sanidad Animal. Universidad Nacional de Mar del Plata; ArgentinaFil: Gioffre, Andrea. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET); Argentin

Evaluación por ELISA en leche para la detección de anticuerpos frente a Mycobacterium avium subsp. paratuberculosis

Mycobacterium avium subsp. paratuberculosis (MAP) es el agente causal de la paratuberculosis (PTBC). Afecta a rumiantes domésticos y especies silvestres causando enteritis granulomatosa. La prueba más utilizada para su diagnóstico es el ELISA (Enzime-linked ImmunoSorbent Assay) debido a su bajo costo y rápido tiempo de procesamiento, aunque la sensibilidad depende del estadio clínico del animal.Trabajo publicado en Cagliada, Maria del Pilar Lilia y Galosi, Cecilia Mónica (comps.). I Congreso de Microbiología Veterinaria. Libro de resúmenes. La Plata: Facultad de Ciencias Veterinarias, 2021.Facultad de Ciencias Veterinaria

Phylogenomic analysis for Campylobacter fetus ocurring in Argentina

Background and Aim: Campylobacter fetus is one of the most important pathogens that severely affects livestock industry worldwide. C. fetus mediated bovine genital campylobacteriosis infection in cattle has been associated with significant economic losses in livestock production in the Pampas region, the most productive area of Argentina. The present study aimed to establish the genomic relationships between C. fetus strains, isolated from the Pampas region, at local and global levels. The study also explored the utility of multi‐locus sequence typing (MLST) as a typing technique for C. fetus. Materials and Methods: For pangenome and phylogenetic analysis, whole genome sequences for 34 C. fetus strains, isolated from cattle in Argentina were downloaded from GenBank. A local maximum likelihood (ML) tree was constructed and linked to a Microreact project. In silico analysis based on MLST was used to obtain information regarding sequence type (ST) for each strain. For global phylogenetic analysis, a core genome ML‐tree was constructed using genomic dataset for 265 C. fetus strains, isolated from various sources obtained from 20 countries. Results: The local core genome phylogenetic tree analysis described the presence of two major clusters (A and B) and one minor cluster (C). The occurrence of 82% of the strains in these three clusters suggested a clonal population structure for C. fetus. The MLST analysis for the local strains revealed that 31 strains were ST4 type and one strain was ST5 type. In addition, a new variant was identified that was assigned a novel ST, ST70. In the present case, ST4 was homogenously distributed across all the regions and clusters. The global analysis showed that most of the local strains clustered in the phylogenetic groups that comprised exclusively of the strains isolated from Argentina. Interestingly, three strains showed a close genetic relationship with bovine strains obtained from Uruguay and Brazil. The ST5 strain grouped in a distant cluster, with strains obtained from different sources from various geographic locations worldwide. Two local strains clustered in a phylogenetic group comprising intercontinental Campylobacter fetus venerealis strains. Conclusion: The results of the study suggested active movement of animals, probably due to economic trade between different regions of the country as well as with neighboring countries. MLST results were partially concordant with phylogenetic analysis. Thus, this method did not qualify as a reliable subtyping method to assess C. fetus diversity in Argentina. The present study provided a basic platform to conduct future research on C. fetus, both at local and international levels.Fil: Farace, Pablo Daniel. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación En Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Irazoqui, José Matías. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Santa Fe. Instituto de Investigacion de la Cadena Lactea. - Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Santa Fe. Estacion Experimental Agropecuaria Rafaela. Instituto de Investigacion de la Cadena Lactea.; ArgentinaFil: Morsella, Claudia Graciela. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: García, Juan Agustín. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Méndez, Maria Alejandra. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Paolicchi, Fernando Alberto. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Amadio, Ariel Fernando. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Santa Fe. Instituto de Investigacion de la Cadena Lactea. - Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Santa Fe. Estacion Experimental Agropecuaria Rafaela. Instituto de Investigacion de la Cadena Lactea.; ArgentinaFil: Gioffré, Andrea Karina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación En Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentin

A novel real-time PCR assay for quantitative detection of Campylobacter fetus based on ribosomal sequences

Background: Campylobacter fetus is a pathogen of major concern for animal and human health. The species shows a great intraspecific variation, with three subspecies: C. fetus subsp. fetus, C. fetus subsp. venerealis, and C. fetus subsp. testudinum. Campylobacter fetus fetus affects a broad range of hosts and induces abortion in sheep and cows. Campylobacter fetus venerealis is restricted to cattle and causes the endemic disease bovine genital campylobacteriosis, which triggers reproductive problems and is responsible for major economic losses. Campylobacter fetus testudinum has been proposed recently based on genetically divergent strains isolated from reptiles and humans. Both C. fetus fetus and C. fetus testudinum are opportunistic pathogens for immune-compromised humans. Biochemical tests remain as the gold standard for identifying C. fetus but the fastidious growing requirements and the lack of reliability and reproducibility of some biochemical tests motivated the development of molecular diagnostic tools. These methods have been successfully tested on bovine isolates but fail to detect some genetically divergent strains isolated from other hosts. The aim of the present study was to develop a highly specific molecular assay to identify and quantify C. fetus strains. Results: We developed a highly sensitive real-time PCR assay that targets a unique region of the 16S rRNA gene. This assay successfully detected all C. fetus strains, including those that were negative for the cstA gene-based assay used as a standard for molecular C. fetus identification. The assay showed high specificity and absence of cross-reactivity with other bacterial species. The analytical testing of the assay was determined using a standard curve. The assay demonstrated a wide dynamic range between 102 and 107 genome copies per reaction, and a good reproducibility with small intra- and inter-assay variability. Conclusions: The possibility to characterize samples in a rapid, sensitive and reproducible way makes this assay a good option to establish a new standard in molecular identification and quantification of C. fetus species.EEA BalcarceFil: Iraola, Gregorio. Universidad de la República. Facultad de Ciencias. Sección Genética Evolutiva; Uruguay. Institut Pasteur Montevideo. Unidad de Bioinformática; UruguayFil: Pérez, Ruben. Universidad de la República. Facultad de Ciencias. Sección Genética Evolutiva; UruguayFil: Betancor, Laura. Universidad de la República. Facultad de Medicina. Instituto de Higiene. Departamento de Bacteriología y Virología; UruguayFil: Marandino, Ana. Universidad de la República. Facultad de Ciencias. Sección Genética Evolutiva; UruguayFil: Morsella, Claudia Graciela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Laboratorio de Bacteriología. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Mendez, Maria Alejandra. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Laboratorio de Bacteriología. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Paolicchi, Fernando. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Laboratorio de Bacteriología. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Piccirillo, Alessandra. Università degli Studi di Padova. Dipartimento di Biomedicina Comparata e Alimentazione; ItaliaFil: Tomás, Gonzalo. Universidad de la República. Facultad de Ciencias. Sección Genética Evolutiva; UruguayFil: Velilla, Alejandra Vanesa. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Laboratorio de Bacteriología. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Calleros, Lucía. Universidad de la República. Facultad de Ciencias. Sección Genética Evolutiva; Urugua

Evaluation of direct immunofluerescence test for Campylobacter fetus in bull experimentally infected and commensal bacteria from the reproductive tract of bulls

Campylobacter fetus is a Gram negative bacterium, with 2 relevant subspecies for cattle health: C. fetus subsp. fetus (Cff) and C. fetus subsp. venerealis (Cfv) which cause important reproductive losses. In the present work, four groups of bulls were used: one group to characterize the genital microbiota (G1; n=3) and the other three to evaluate the direct immunofluorescence (DIF) test for the diagnosis of bovine campylobacteriosis in preputial samples (PS) from experimentally infected bulls with Cff (G2; n=3) and Cfv (G3; n=3), and controls (G4; n=4). Seven bacterial strains of different genera were identified in the PS from G1. Other 11 laboratory bacterial strains were included: Cff, Cfv and Cfv biovar Intermedius, 3 Campylobacter non-fetus, 3 Gram negative and 2 Gram positive. Only the C. fetus strains presented positive immunostaining. The sensitivity and specificity of the DIF test were 79 % and 100 %, respectively. Concordance between DIF test and bacteriological culture was 83 % (Kappa index: 0.65). The present study shows the high specificity of the DIF test for detection of C. fetus using a fluorescent conjugate elaborated in Argentina, and highlights the relevance of no cross reaction against 15 bacterial strains normally present in bull preputial microbiota.Campylobacter fetus es una bacteria Gram negativa que incluye 2 subespecies de relevancia sanitaria para el bovino: C. fetus subsp. fetus (Cff) y C. fetus subsp. venerealis (Cfv), causantes de importantes pérdidas reproductivas. En el presente estudio, se utilizaron cuatro grupos de toros: un grupo (G1) para caracterizar la microbiota genital, y otros tres (G2, G3, G4) (n=10) para evaluar el test de inmunofluorescencia directa (IFD) para el diagnóstico de la campilobacteriosis bovina en esmegma prepucial (EP) de toros experimentalmente infectados con Cff y Cfv. Se identificaron siete cepas bacterianas de distinto género del G1. Otras 11 cepas bacterianas de laboratorio fueron incluidas: Cff, Cfv, Cfv biovar Intermedius, 3 Campylobacter no-fetus, 3 Gram negativo y 2 Gram positivo. Solo las cepas de C. fetus presentaron inmunofluorescencia positiva. La sensibilidad y especificidad de la IFD fue de 79 % y 100 %, respectivamente. La concordancia entre la IFD y el cultivo bacteriológico fue de 83 % (Kappa: 0,65). Se demuestra la alta especificidad de la IFD para la detección de C. fetus con un conjugado fluorescente elaborado en Argentina, y se destaca la no reacción cruzada contra 15 cepas bacterianas normalmente presentes en la microbiota prepucial del toro.Fil: García, Juan Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible - Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; ArgentinaFil: Soto, J.. Laboratorio Biologico de Tandil ; ArgentinaFil: Soto, P.. Laboratorio Biologico de Tandil Srl.; ArgentinaFil: Malena, Rosana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible - Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; ArgentinaFil: Morsella, Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible - Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; ArgentinaFil: Méndez, Maria Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible - Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; ArgentinaFil: Fiorentino, Maria Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible - Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; ArgentinaFil: Paz Acuña, Joaquín Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible - Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; ArgentinaFil: Lucchesi, Enrique. Laboratorio Biologico de Tandil ; ArgentinaFil: Paolicchi, Fernando Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible - Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible; Argentin

Report of mycobacteria isolated from domestic and wildlife species during 2004-2008

La identificación de la tuberculosis bovina y su diferenciación de las micobacteriosis es fundamental durante el diagnóstico. Es por eso que los laboratorios especializados en micobacterias son de suma importancia en los servicios de salud pública y salud animal. El objetivo de la presente investigación es diferenciar Mycobacterium bovis de micobacterias no tuberculosas en cepas cultivadas a partir de especies domésticas y silvestres de siete provincias de Argentina durante 2004-2008. La diferenciación se basó sobre las pruebas bioquímicas, las características fenotípicas y el “spolygotyping” de M. bovis. Con la identificación bioquímica y fenotípica se detectaron 20 cepas de M. bovis, 18 de las cuales fueron confirmadas mediante “spolygotyping”, y 34 cepas de micobacterias no tuberculosas. Trece especies fueron caracterizadas y todas ellas fueron agrupadas considerando el riesgo biológico y el potencial patógeno notificado en seres humanos y/o animales. En este trabajo se han logrado avances en el diagnóstico de tuberculosis y micobacteriosis en medicina veterinaria. En este área el diagnóstico habitualmente se basa sobre la observación micro y macroscópica de los tubérculos y los resultados de la intradermorreacción. Estos avances son importantes porque la tuberculosis zoonótica aún es un problema de salud pública en América Latina.Detection and identification of bovine tuberculosis and its differentiation from micobacteriosis is fundamental during diagnoses. That is why mycobacteria laboratories improvement becomes essential in public health and veterinary medicine services. The objective of the present research is to differentiate Mycobacterium bovis and nontuberculous mycobacterias in isolates cultured from domestic and wildlife species from seven Argentinean provinces during 2004-2008. Differentiation was based on biochemical tests, phenotypic characteristics and M. bovis spolygotyping. Biochemical and phenotypic identification resulted in 20 M. bovis strains, 18 of them were confirmed by spolygotyping, and 34 nontuberculous mycobacteria strains. Thirteen species were characterized and all of them were grouped considering biological risk and pathogenic potential reported in humans and/or animals. Here we have reached advances in tuberculosis and micobacteriosis diagnoses in veterinary medicine. In this area diagnoses are often based on micro and macroscopic observation of the tubercles and skin test results. These advances are not minor as zoonotic tuberculosis is still a public health problem in Latin America.Facultad de Ciencias Veterinaria

Molecular typing of Argentinian <i>Mycobacterium avium</i> subsp. <i>paratuberculosis</i> isolates by multiple-locus variable number-tandem repeat analysis

Multiple-locus variable number-tandem repeat analysis (MLVA) of Mycobacterium avium subspecies paratuberculosis (MAP) isolates may contribute to the knowledge of strain diversity in Argentina. Although the diversity of MAP has been previously investigated in Argentina using IS900-RFLP, a small number of isolates were employed, and a low discriminative power was reached. The aim of the present study was to test the genetic diversity among MAP isolates using an MLVA approach based on 8 repetitive loci. We studied 97 isolates from cattle, goat and sheep and could describe 7 different patterns: INMV1, INMV2, INMV11, INMV13, INMV16, INMV33 and one incomplete pattern. INMV1 and INMV2 were the most frequent patterns, grouping 76.3% of the isolates. We were also able to demonstrate the coexistence of genotypes in herds and co-infection at the organism level. This study shows that all the patterns described are common to those described in Europe, suggesting an epidemiological link between the continents.Facultad de Ciencias Veterinaria

Molecular typing of Argentinian <i>Mycobacterium avium</i> subsp. <i>paratuberculosis</i> isolates by multiple-locus variable number-tandem repeat analysis

Multiple-locus variable number-tandem repeat analysis (MLVA) of Mycobacterium avium subspecies paratuberculosis (MAP) isolates may contribute to the knowledge of strain diversity in Argentina. Although the diversity of MAP has been previously investigated in Argentina using IS900-RFLP, a small number of isolates were employed, and a low discriminative power was reached. The aim of the present study was to test the genetic diversity among MAP isolates using an MLVA approach based on 8 repetitive loci. We studied 97 isolates from cattle, goat and sheep and could describe 7 different patterns: INMV1, INMV2, INMV11, INMV13, INMV16, INMV33 and one incomplete pattern. INMV1 and INMV2 were the most frequent patterns, grouping 76.3% of the isolates. We were also able to demonstrate the coexistence of genotypes in herds and co-infection at the organism level. This study shows that all the patterns described are common to those described in Europe, suggesting an epidemiological link between the continents.Facultad de Ciencias Veterinaria