The aim of this study was to determine the expression of antimicrobial peptides (α- and β-defensins) in the intestinal epithelium of newborn alpaca (1 to 6 weeks of age) with enteropathies, using the relative quantification of messenger RNA (mRNA) of the α (Defa 8) and β (β def alp) defensins. Two portions of the jejunum (2 cm) were collected from 29 newborn alpaca with signs of diarrhea. One portion was processed for histological analysis using hematoxylin-eosin staining to determine the type of enteropathy. The second portion was used to obtain total mRNA from jejunal scrapings, which served as template for cDNA synthesis by reverse transcription (RT), followed by a Real-Time PCR for the amplification and detection of defensins. The relative quantification of mRNA was performed using 2-ΔΔCt method. The sick newborn showed an expression of α-defensin (Defa 8) corresponding to 18...

Leptospirosis is an important bacterial zoonosis worldwide. Dogs and other animals can be infected, constituting an important role in the spread of the bacteria to humans. The infection is caused by any of the pathogenic serovars of the 25 serogroups of Leptospira spp. The aim of this study was to identify serogroups of Leptospira spp in dogs that had presumptive diagnosis of leptospirosis. A total of 305 serum samples were obtained from dogs in 31 districts of Lima. The microagglutination test (MAT) was performed, establishing > 1/100 seroreactivity titre as seropositive using reference strains of the 25 serogroups, including the new Iquitos serogroup, Varillal serovar, strain Var10, isolated and reported in human cases in Peru. The frequency of seropositive samples was 58.0% and 10.2% were co-agglutinations. The seropositive reacted against 18 serogroups and the most frequent were: ...

Escherichia coli is associated with diarrhoea that can cause death in young alpacas. Patotypes of E. coli use the fimbriae to adhere to the host in the first stage of pathogenesis. Therefore, the present study aimed to develop and produce a recombinant protein of E. coli fimbrial adhesin F17 and to evaluate its immunogenicity in alpaca peripheral blood mononuclear cells (PBMC). BL21 was used as an expression vector, the recombinant protein was purified by immobilized affinity chromatography and the production of PBMC cytokines was evaluated 48 and 72 hours after the challenge with F17. The results indicate a significant increase in the production of Th1/Th2 cytokines, predominantly IFN-γ and IL-4. Therefore, the BL21-F17 mixture could be considered as a potential vaccine candidate for the prevention of diarrhoea in alpacas produced by E. coli.

El objetivo del presente estudio fue determinar la expresión de péptidos antimicrobianos (á- y â-defensinas) en el epitelio intestinal de crías de alpaca de 1 a 6 semanas de edad y con enteropatías, mediante la cuantificación relativa de ARN mensajeros (ARNm) de las á (defa 8) y â (â def alp) defensinas. Se tomaron dos porciones de yeyuno de 2 cm de longitud de 29 crías de alpacas con signos de diarrea. Una porción se procesó para el análisis histopatológico utilizando la tinción Hematoxilina-Eosina para determinar el tipo de enteropatía. De la otra porción se obtuvo el ARNm total de los raspados yeyunales, que sirvió de molde para la síntesis de cDNA mediante transcripción reversa (RT), seguido de un PCR en Tiempo Real, para la amplificación y detección de las defensinas. La cuantificación relativa de ARNm se realizó mediante el método 2- ÄÄCt. Las crías enf...

Leptospirosis is an important bacterial zoonosis worldwide. Dogs and other animals can be infected, constituting an important role in the spread of the bacteria to humans. The infection is caused by any of the pathogenic serovars of the 25 serogroups of Leptospira spp. The aim of this study was to identify serogroups of Leptospira spp in dogs that had presumptive diagnosis of leptospirosis. A total of 305 serum samples were obtained from dogs in 31 districts of Lima. The microagglutination test (MAT) was performed, establishing > 1/100 seroreactivity titre as seropositive using reference strains of the 25 serogroups, including the new Iquitos serogroup, Varillal serovar, strain Var10, isolated and reported in human cases in Peru. The frequency of seropositive samples was 58.0% and 10.2% were co-agglutinations. The seropositive reacted against 18 serogroups and the most frequent were: ...

Escherichia coli is associated with diarrhoea that can cause death in young alpacas. Patotypes of E. coli use the fimbriae to adhere to the host in the first stage of pathogenesis. Therefore, the present study aimed to develop and produce a recombinant protein of E. coli fimbrial adhesin F17 and to evaluate its immunogenicity in alpaca peripheral blood mononuclear cells (PBMC). BL21 was used as an expression vector, the recombinant protein was purified by immobilized affinity chromatography and the production of PBMC cytokines was evaluated 48 and 72 hours after the challenge with F17. The results indicate a significant increase in the production of Th1/Th2 cytokines, predominantly IFN-γ and IL-4. Therefore, the BL21-F17 mixture could be considered as a potential vaccine candidate for the prevention of diarrhoea in alpacas produced by E. coli.

The aim of this study was to identify the Leptospira spp serogroups present in alpacas from the Maranganí Experimental Station of the IVITA Research Center in Cusco, Peru. Blood samples from 126 alpacas older than one year of age were collected and analyzed by the serological microagglutination test (MAT). Serovars of international reference of 21 pathogenic serogroups were used. Results showed that 42.9% (34.51- 51.7%) of alpacas were seropositive to nine pathogenic serogroups: Icterohaemorrhagiae (12.7%), Pomona (11.1%), Panama (11.1%), Hurstbridge (9.5%), Ranarum (5.6%), Ballum (1.6%), Cypnopteri (1.6), Djasiman (0.8%) and Hebdomadis (0.8%). Likewise, 2.4% (3/126) of coagglutinations were obtained.

El objetivo del estudio fue identificar los serogrupos de Leptospira spp presentes en alpacas de la estación experimental Maranganí del Centro de Investigación IVITA, Cusco, Perú. Se recolectaron 126 muestras de sangre de alpacas mayores a un año y se analizaron mediante la prueba serológica de microaglutinación (MAT), utilizando serovares de referencia internacional de 21 serogrupos patógenos. Se determinó que el 42.9% (34.5- 51.7%) de las alpacas fueron seropositivas a nueve serogrupos patógenos: Icterohaemorrhagiae (12.7%), Pomona (11.1%), Panama (11.1%), Hurtsbridge (9.5%), Ranarum (5.6%), Ballum (1.6%), Cypnopteri (1.6), Djasiman (0.8%) y Hebdomadis (0.8%). Asimismo, se obtuvo el 2.4% (3/126) de coaglutinaciones.

The coagulase-positive staphylococci (CoPS) group includes the species S. aureus, S. pseudintermedius, S. intermedius and S. schleiferi subsp. coagulans. The purpose of this study was to evaluate the antimicrobial resistance of CoPS isolated from dogs with external otitis, using the most commonly antibiotics prescribed in the daily clinic to treat this disease. Samples of ear secretions (n=148) were obtained from 104 dogs with external otitis treated in a veterinary clinic in Lima, Peru in a period of six months. Among them, 113 isolates were identified as Staphylococcus sp, of which 105 were CoPS. The isolates showed the greatest resistance to resistance to ciprofloxacin (27.4%) and the greatest sensitivity to nitrofurantoin (82.1%).

The coagulase-positive staphylococci (CoPS) group includes the species S. aureus, S. pseudintermedius, S. intermedius and S. schleiferi subsp. coagulans. The purpose of this study was to evaluate the antimicrobial resistance of CoPS isolated from dogs with external otitis, using the most commonly antibiotics prescribed in the daily clinic to treat this disease. Samples of ear secretions (n=148) were obtained from 104 dogs with external otitis treated in a veterinary clinic in Lima, Peru in a period of six months. Among them, 113 isolates were identified as Staphylococcus sp, of which 105 were CoPS. The isolates showed the greatest resistance to resistance to ciprofloxacin (27.4%) and the greatest sensitivity to nitrofurantoin (82.1%).

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 la detección de los genes de resistencia a los antibióticos en aislados de Escherichia coli obtenidos de cerdos con cuadros diarreicos granjas tecnificadas de Lima Metropolitana desde 2017 hasta 2020. Se evaluaron 119 aislados de E. coli. Los aislados fueron reactivados para extraer el ADN y detectar los genes de resistencia a los principales antibióticos y de mayor importancia en la industria porcina, tales como las tetraciclinas (tetA, tetB y tetC), sulfonamidas (sul1, sul2 y sul3), estreptomicina-espectinomicina (strA/strB, aadA) y apramicina (aac(3)IV) mediante la Reacción en Cadena de Polimerasa (PCR) convencional. El 98.3% (117/119) de los aislados fueron positivos a por lo menos un gen de resistencia antimicrobiana, especialmente al grupo de las tetraciclinas (88.2%). De los 10 genes de resistencia antimicrobiana considerados, el gen tetA tuvo la ...

The aim of this study was to detect the frequency of Salmonella sp by isolation techniques in pork carcasses intended for human consumption. Three hundred carcasses from two slaughterhouses in Lima, Peru were studied. Samples were taken by swabbing the skin of the head, abdomen, back and leg, representing 1200 subsamples. They were taken to the laboratory in Falcon tubes with buffered peptone water, and processed following the protocol for isolation of bacteria based on ISO 6579:2002. The isolates were identified by biochemical tests and specific antisera. In 6.3 ± 2.4% (19/300) of carcasses and 1.8% (21/1200) of subsamples were detected Salmonella sp. The highest frequencies of isolates were obtained from the head (33.3%, 7/21) and the abdomen (33.3%, 7/21). The isolates were serotyped and identified as Salmonella enterica subesp. enterica serotype Derby. The results confirm the need t...

The aim of this study was to detect the frequency of Salmonella sp by isolation techniques in pork carcasses intended for human consumption. Three hundred carcasses from two slaughterhouses in Lima, Peru were studied. Samples were taken by swabbing the skin of the head, abdomen, back and leg, representing 1200 subsamples. They were taken to the laboratory in Falcon tubes with buffered peptone water, and processed following the protocol for isolation of bacteria based on ISO 6579:2002. The isolates were identified by biochemical tests and specific antisera. In 6.3 ± 2.4% (19/300) of carcasses and 1.8% (21/1200) of subsamples were detected Salmonella sp. The highest frequencies of isolates were obtained from the head (33.3%, 7/21) and the abdomen (33.3%, 7/21). The isolates were serotyped and identified as Salmonella enterica subesp. enterica serotype Derby. The results confirm the need t...

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 compare the relative expression levels of the gene from exon 1 of the IgA in the intestinal epithelium of baby alpacas untreated and treated orally with Clostridium perfringens antigens and all-trans retinoic acid (ATRA). Thirty two animals were sampled: 14 treated (6 of 1 day old and 8 between 7-14 days old) and 18 untreated (10 of 1 day old and 8 between 7-14 days old). The animals were slaughtered after one week of the treatment and 2 cm of the jejunum was collected and kept at -196 °C. Total RNA was extracted from each sample using the TRIzol® method and complementary DNA (cDNA) was synthesized. PCR and RT-PCR Real Time were conducted using specific oligonucleotides designed for the detection of exon 1 of the region Fc IgA in the alpaca. The quantification of the relative expression by normalization with GAPDH gene mRNA and the relative expression calcu...

El objetivo del estudio fue comparar los niveles de expresión relativa del gen del exón 1 de la IgA en el epitelio intestinal de las crías de alpacas tratadas y no tratadas con antígenos de Clostridium perfringens más ácido holotransretinoico (ATRA) por vía oral. Se muestrearon 32 animales: 14 tratados (6 de 1 día de edad y 8 entre 7 a 14 días de edad) y 18 no tratados (10 de 1 día de edad y 8 entre 7 a 14 días de edad). Los animales fueron sacrificados a la semana del tratamiento, se recolectó un segmento de 2 cm de yeyuno y se almacenó a -196 °C. De cada muestra se realizó la extracción de ARN total con el método de TRIzol® y luego se realizó la técnica del RT PCR a tiempo real empleando oligonucleótidos diseñados para la detección del exón 1 del gen de inmunoglobulina A (IgA) de alpaca. La cuantificación de la expresión relativa mediante normalización con AR...

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...