This study aimed to standardize a TaqMan Real-Time PCR assay to detect the presence of pathogenic leptospires in urine samples of a dog infected in vitro with standard strains of Leptospira spp. Samples were obtained from a clinically healthy dog, negative to the microagglutination test. Lepto R and Lepto F primers, specific for Leptospira sp and a Lepto TaqMan probe were used, which amplified and hybridized respectively a portion of the rrs gene, differentiating between pathogenic and nonpathogenic species of Leptospira. Thermocycling program was standardized with 35 cycles of 95 °C for 15 s and 60 °C for 1 min with an initial cycle of 95 °C for 5 min. Cycle threshold (Ct) values determined during the standardization of PCR were from 12.53 to 18.21 for the 25 pathogenic strains of Leptospira sp. In contrast, saprophytic Leptospira and other species of bacteria did not produce any spe...

El presente estudio tuvo como objetivo estandarizar una técnica de PCR en tiempo real con sondas TaqMan para detectar la presencia de leptospiras patógenas en orina de perro infectada in vitro con cepas patrón de Leptospira sp. Las muestras fueron obtenidas de un perro clínicamente sano y negativo a la prueba de microaglutinación. Se utilizaron los cebadores Lepto R y Lepto F, específicos para Leptospira sp y una sonda TaqMan Lepto probe que amplifican e hibridan, respectivamente, una porción del gen rrs, capaces de diferenciar entre especies patógenas y no patógenas de Leptospira. Se estandarizó el protocolo de PCR en 35 ciclos, con un proceso de desnaturalización inicial a 95 °C por 5 min, seguida por una desnaturalización a 95 °C por 15 s y finalmente el alineamiento y extensión en un solo paso a 60 °C por 1 min. Los valores de ciclo umbral (Ct) determinados durante la...

El estudio tuvo como objetivo determinar mediante la electroforesis en gel de campo pulsado (PFGE) el porcentaje de similaridad de los perfiles genéticos (pulsotipos) de los serovares de Salmonella no tifoidea aislados de humanos y productos aviares, para conocer la relación de estos. Para ello, se obtuvieron 49 aislados bacterianos de serovares de Salmonella no tifoidea obtenidos de casos clínicos humanos y productos aviares (huevos comerciales, carcasa de pollo de engorde, vísceras y muestras ambientales de granja), los cuales se caracterizaron genéticamente mediante electroforesis en gel de campo pulsado. Con ayuda del programa Bionumerics 7.0. se generó un dendrograma que muestra la relación XbaI – perfiles electroforesis en gel de campo pulsado para las salmonelas en estudio. El análisis de las bandas generadas se realizó mediante el uso del método de UPGM (Unweighted Pa...

La leptospirosis es una enfermedad zoonótica de importancia mundial en salud pública. La enfermedad en humanos está asociada a la presencia de la bacteria Leptospira spp. en los animales, en las zonas urbanas los animales domésticos como el perro juegan un rol importante en la transmisión de la enfermedad. Los caninos domésticos pueden desarrollar la enfermedad o ser portadores asintomáticos que eliminan la bacteria en grandes cantidades en la orina. El presente estudio tuvo como objetivo estandarizar e implementar una técnica de PCR en tiempo real con sondas TaqMan para detectar la presencia de leptospiras patógenas en muestras de orina de caninos domésticos infectadas experimentalmente con cepas patrón de Leptospira spp. Las muestras de orina fueron obtenidas de un perro clínicamente sano y negativo a la prueba de microaglutinación (MAT). Se utilizaron los cebadores Lepto ...

The aim of this study was to detect the antimicrobial resistance mechanisms of 36 Escherichia coli isolates to beta-lactams, quinolones and aminoglycosides using the Kirby-Bauer technique. Thirty-six E. coli isolates from pigs of technified production farms obtained during the 2010-2015 period were used. Fifteen antimicrobials of importance in human and veterinary medicine were tested. The isolates showed resistance mainly to nalidixic acid (89%, 32/36), cloxacillin (83%, 30/36) and amoxicillin-clavulanic acid (69%, 25/36). Only 3% (1/36) were AmpC producers, 42% (15/36) showed a possible mutation in gyrA and 14% (5/36) at least two possible mutations in gyrA or gyrA+parC. In addition, 33% (12/36) showed high probabilities of presence of qnr genes. The enzymes associated to aminoglycoside resistance mechanism were positive in 39% (14/36) to AAC (6’), 28% (10/36) to ANT (2") and 11% (4/...

The aim of this study was to detect the antimicrobial resistance mechanisms of 36 Escherichia coli isolates to beta-lactams, quinolones and aminoglycosides using the Kirby-Bauer technique. Thirty-six E. coli isolates from pigs of technified production farms obtained during the 2010-2015 period were used. Fifteen antimicrobials of importance in human and veterinary medicine were tested. The isolates showed resistance mainly to nalidixic acid (89%, 32/36), cloxacillin (83%, 30/36) and amoxicillin-clavulanic acid (69%, 25/36). Only 3% (1/36) were AmpC producers, 42% (15/36) showed a possible mutation in gyrA and 14% (5/36) at least two possible mutations in gyrA or gyrA+parC. In addition, 33% (12/36) showed high probabilities of presence of qnr genes. The enzymes associated to aminoglycoside resistance mechanism were positive in 39% (14/36) to AAC (6’), 28% (10/36) to ANT (2") and 11% (4/...

El objetivo del estudio fue detectar fenotípicamente los mecanismos de resistencia antimicrobiana de 36 aislados de Escherichia coli a betalactámicos, quinolonas y aminoglucósidos mediante la técnica de Kirby-Bauer. Se utilizaron 36 aislados de E. coli procedentes de porcinos de granjas tecnificadas, obtenidos durante el periodo 2010-2015. Se utilizaron 15 antimicrobianos de importancia en medicina humana y veterinaria. Se detectó resistencia principalmente al ácido nalidíxico (89%, 32/36), cloxacilina (83%, 30/36) y amoxicilina-ácido clavulánico (69%, 25/36). Solo un 3% (1/36) presentó AmpC inducible, 42% (15/36) evidenció una posible mutación en gyrA y el 14% (5/36) al menos dos posibles mutaciones en gyrA o gyrA+parC. Además, el 33% (12/36) evidenció altas probabilidades de presencia de genes qnr. Las enzimas del mecanismo de resistencia a aminoglucósidos fueron positiv...

Pyoderma is one of the most diagnosed skin diseases in canines. Among the agents most involved were Staphylococcus intermedius; however, in 2005 it was reclassified into three phenotypically similar species: S. intermedius, S. pseudintermedius and S. delphini, which cannot be identified by conventional biochemistry. Various studies report S. pseudintermedius as the most frequently isolated bacterial agent in pyoderma. Therefore, this study evaluated the presence of S. pseudintermedius using PCR-RFLP in 141 Staphylococcus sp isolates in the Laboratory of Bacteriology of the Faculty of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, Lima, Perú from cases of canine pyoderma in the period 2016-2018, finding that 87.9% of Staphylococcus sp isolates have been identified as S. pseudintermedius and 12.1% as Staphylococcus sp.

Pyoderma is one of the most diagnosed skin diseases in canines. Among the agents most involved were Staphylococcus intermedius; however, in 2005 it was reclassified into three phenotypically similar species: S. intermedius, S. pseudintermedius and S. delphini, which cannot be identified by conventional biochemistry. Various studies report S. pseudintermedius as the most frequently isolated bacterial agent in pyoderma. Therefore, this study evaluated the presence of S. pseudintermedius using PCR-RFLP in 141 Staphylococcus sp isolates in the Laboratory of Bacteriology of the Faculty of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, Lima, Perú from cases of canine pyoderma in the period 2016-2018, finding that 87.9% of Staphylococcus sp isolates have been identified as S. pseudintermedius and 12.1% as Staphylococcus sp.

The aim of this study was to molecularly and serologically identify Salmonella spp present in isolates from avian eggs, carcasses, and viscera. In total, 46 isolates of avian origin identified as Salmonella spp were evaluated through cultures and biochemical tests in the period 2012-2017 from various districts of Lima. These isolates are kept in the Bacteriology Laboratory stock of the Universidad Nacional Mayor de San Marcos. The strains were reactivated, and suspicious Salmonella spp colonies were reconfirmed by culturing on selective media. Subsequently, the PCR was performed on the suspicious samples as a method of genetic diagnosis of Salmonella. The invasiveness gene invA, a gene involved with the virulence of Salmonella, was detected. Serotyping was performed with polyvalent and monovalent antisera for serogroup and serovar in the Enteropathogens Laboratory of the National Institu...