RESUMEN
Several species of Mycoplasma and Ureaplasma diversum can cause diseases in dairy cattle, which can be associated or not with clinical manifestations. In our country, the presence of Mycoplasma bovis, Mycoplasma californicum and Mycoplasma canadense has been detected, being the only mycoplasma species identified so far. The objective of this study was to identify other species of the Mycoplasmataceae family. Thirty-five Mycoplasma spp.-like isolates obtained from different samples from cattle, with or without clinical symptoms, from eight herds located in the provinces of Santa Fe, Cordoba, Buenos Aires and San Luis were utilized in the present study. Through the use of species-specific polymerase chain reactions (PCR) Mycoplasma bovigenitalium, Mycoplasma alkalescens, Mycoplasma bovirhinis and U. diversum were identified and through amplification and further sequencing of the 16-23S rRNA intergenic spacer regions, Mycoplasma arginine and M. californicum were identified. The identification of these species represents an important advance in knowledge in order to include these pathogens in the differential diagnosis of certain clinical and pathological entities of cattle from Argentina.
Asunto(s)
Enfermedades de los Bovinos , Mycoplasma , Ureaplasma , Animales , Argentina , Bovinos , Enfermedades de los Bovinos/diagnóstico , Enfermedades de los Bovinos/microbiología , Mycoplasma/genética , Mycoplasma/aislamiento & purificación , Infecciones por Mycoplasma/veterinaria , Reacción en Cadena de la Polimerasa , Ureaplasma/genética , Ureaplasma/aislamiento & purificación , Infecciones por Ureaplasma/veterinariaRESUMEN
Few studies have described the relationship between genotypic and phenotypic methods for detecting penicillin resistance in Staphylococcus aureus isolated from bovine intramammary infection (IMI). Six phenotypic methods for penicillinase detection were compared with a genotypic method testing the presence of the ß-lactamase gene blaZ in Staph. aureus (n = 150) isolated from bovine IMI. Highest sensitivities and specificities were observed for disk diffusion (DD) (93 and 97.4%), minimum inhibitory concentration (MIC) (90.3 and 97.4%), Cefinase™ (85.9 and 97.4%) and Diatabs™ (85.7 and 98.7%). The estimated cut-off points estimated in the present study can be considered close to the ones indicated by CLSI (2013). The molecular detection of blaZ gene is the only method that may indicate the real or potential capacity of producing ß-lactamase in Staph. aureus. Considering that from a clinical standpoint a false negative result from a phenotypic test is the most unfavourable situation, a combination of standard DD with Diatabs™ or Cefinase™ should be performed by routine mastitis laboratories to minimise false negative results.
Asunto(s)
Mastitis Bovina/microbiología , Penicilina G , Resistencia a las Penicilinas , Staphylococcus aureus/enzimología , beta-Lactamasas/genética , Animales , Bovinos , ADN Bacteriano/análisis , Reacciones Falso Negativas , Femenino , Genotipo , Pruebas de Sensibilidad Microbiana , Penicilinasa/análisis , Fenotipo , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/genéticaRESUMEN
Different species of Mycoplasma can affect bovine cattle, causing several diseases. PCR sequencing and further analysis of the 16S-23S rRNA ITS region have shown a significant interspecies variability among Mollicutes. Sixteen suspected isolates of Mycoplasma spp. obtained from milk samples from dairy herds were amplified (16S-23S rRNA ITS region). Fourteen out of those 16 suspected Mycoplasma spp. isolates were PCR-positive. To confirm the identity of Mycoplasma bovis, these 14 isolates were tested by another species-specific PCR. Seven of the isolates rendered a positive result. The products of 16S-23S rRNA ITS PCR from one isolate that was identified as M. bovis and from two other isolates, identified as non- M. bovis were randomly selected, sequenced and analyzed. The three sequences (A, B and C) showed 100% similarity with M. bovis, Mycoplasma canadense and Mycoplasma californicum respectively.
Asunto(s)
Bovinos/microbiología , Leche/microbiología , Mycoplasma/aislamiento & purificación , Animales , ArgentinaRESUMEN
Varias especies de Mycoplasma y Ureaplasma diversum pueden causar enfermedades en el ganado bovino lechero, asociadas o no a manifestaciones clínicas. En nuestro país, ha sido detectada la presencia de solo tres especies de este grupo hasta el momento: Mycoplasma bovis, Mycoplasma californicum y Mycoplasma canadense. El objetivo del presente trabajo fue identificar otras especies de la familia Mycoplasmataceae. Se estudiaron treinta y cinco aislamientos compatibles con Mycoplasma spp. obtenidos a partir de diferentes muestras de bovinos, con o sin sintomatología clínica, provenientes de ocho rodeos ubicados en las provincias de Santa Fe, Córdoba, Buenos Aires y San Luis. Mediante el uso de reacciones en cadena de la polimerasa (PCR) específicas de especie se identificaron Mycoplasma bovigenitalum, Mycoplasma alkalescens, Mycoplasma bovirhinis y U. diversum, y mediante la amplificación y posterior secuenciación del espacio intergénico 16-23S ARNr se identificaron Mycoplasma arginini y M. californicum. La identificación de estas especies por primera vez en nuestro país es un hecho de Argentina relevancia, que representa un importante avance en el conocimiento para incluir estos patógenos en el diagnóstico diferencial de determinadas entidades clínico-patológicas de los bovinos de Argentina.
Several species of Mycoplasma and Ureaplasma diversum can cause diseases in dairy cattle, which can be associated or not with clinical manifestations. In our country, the presence of Mycoplasma bovis, Mycoplasma californicum and Mycoplasma canadense has been detected, being the only mycoplasma species identified so far. The objective of this study was to identify other species of the Mycoplasmataceae family. Thirty-five Mycoplasma spp.-like isolates obtained from different samples from cattle, with or without clinical symptoms, from eight herds located in the provinces of Santa Fe, Cordoba, Buenos Aires and San Luis were utilized in the present study. Through the use of species-specific polymerase chain reactions (PCR) Mycoplasma bovigenitalium, Mycoplasma alkalescens, Mycoplasma bovirhinis and U. diversum were identified and through amplification and further sequencing of the 16-23S rRNA intergenic spacer regions, Mycoplasma arginine and M. californicum were identified. The identification of these species represents an important advance in knowledge in order to include these pathogens in the differential diagnosis of certain clinical and pathological entities of cattle from Argentina.
Asunto(s)
Animales , Bovinos , Ureaplasma , Enfermedades de los Bovinos , Mycoplasma , Argentina , Ureaplasma/aislamiento & purificación , Ureaplasma/genética , Enfermedades de los Bovinos/diagnóstico , Enfermedades de los Bovinos/microbiología , Reacción en Cadena de la Polimerasa , Infecciones por Ureaplasma/veterinaria , Mycoplasma/aislamiento & purificación , Mycoplasma/genética , Infecciones por Mycoplasma/veterinariaRESUMEN
Diferentes especies del género Mycoplasma pueden afectar al ganado bovino y causar varias enfermedades. La técnica de PCR, secuenciación y posterior análisis de la región ITS 16S-23S ARNr ha mostrado que existe una importante variabilidad interespecies entre Mollicutes. Se realizó la amplificación (región ITS 16S-23S ARNr) de 16 aislamientos sospechosos de corresponder a alguna especie de Mycoplasma, que habían sido obtenidos de muestras de leche provenientes de rodeos lecheros. Catorce de esos aislamientos fueron PCR positivos. Para confirmar la identidad de Mycoplasma bovis, dichos aislamientos fueron evaluados por otra PCR especie-específica. Siete aislamientos dieron un resultado positivo. Los productos de la PCR de la ITS 16S-23S ARNr de un aislamiento identificado como M. bovis y de otros dos aislamientos identificados como no-M. bovis fueron seleccionados al azar, secuenciados y analizados. Las tres secuencias (A, B y C) mostraron 100 % de similitud con cepas de M. bovis, Mycoplasma canadense y Mycoplasma californicum, respectivamente
Different species of Mycoplasma can affect bovine cattle, causing several diseases. PCR sequencing and further analysis of the 16S-23S rRNA ITS region have shown a significant interspecies variability among Mollicutes. Sixteen suspected isolates of Mycoplasma spp. obtained from milk samples from dairy herds were amplified (16S-23S rRNA ITS region). Fourteen out of those 16 suspected Mycoplasma spp. isolates were PCR-positive. To confirm the identity of Mycoplasma bovis, these 14 isolates were tested by another species-specific PCR. Seven of the isolates rendered a positive result. The products of 16S-23S rRNA ITS PCR from one isolate that was identified as M. bovis and from two other isolates, identified as non- M. bovis were randomly selected, sequenced and analyzed. The three sequences (A, B and C) showed 100% similarity with M. bovis, Mycoplasma canadense and Mycoplasma californicum respectively