Luis Samartino | INTA UNIVERSIDAD DE CHILE (original) (raw)
Papers by Luis Samartino
ABSTRACT Tendo em vista a importância da bubalinocultura como fonte de proteína para o Brasil e t... more ABSTRACT Tendo em vista a importância da bubalinocultura como fonte de proteína para o Brasil e também do Programa Nacional de Controle e Erradicação da Brucelose e da Tuberculose para a evolução das cadeias produtoras de bovinos e bubalinos e, devido à escassez de estudos sobre o sorodiagnóstico da brucelose na espécie bubalina, procedimento no qual se apóia o processo de certificação de rebanhos livres e monitorados, o presente estudo objetivou comparar o desempenho de diferentes testes para o sorodiagnóstico da brucelose nessa espécie. Soros de 696 fêmeas bubalinas adultas foram submetidos aos testes qualitativos BPA, AATE, AAT e quantitativos: SRP, SLT, ELISAI, ELISAC, PF e ME e FC. Foi empregada, gold standard, a combinação de dois testes, FC e ME, considerando dois critérios: a) animais positivos para os reagentes na FC (título=20UI) e no ME (critério para fêmea vacinada) e como negativos os animais não reagentes na FC (título<20UI) e no ME; b) animais positivos os reagentes na FC (título=20UI) e no ME (critério para fêmea não vacinada) e negativos os não reagentes na FC (título<20UI) e no ME. Esta consideração foi necessária em função dos animais não apresentarem histórico de vacinação confiável o que interfere na determinação do ponto de corte a ser utilizado no teste ME de animais vacinados e não vacinados. Desta forma, numa primeira análise todos os animais foram avaliados no ME como vacinados e em outra como não vacinados. C. (Continuação) inferidos para bubalinos com razoável segurança; b) devem ser estabelecidos pontos de corte específicos para búfalos para o SLT, o SRP e o ELISAI; c) as melhores combinações de sensibilidade e especificidade relativas foram alcançadas pelo ELISAC, o PF, o BPA e o AAT; d) os melhores resultados de Kappa foram verificados para o ELISAC (kappa), PF, BPA, AATE e AAT; e) o BPA, AAT e AATE são os melhores testes para o sorodiagnóstico de triagem em bubalinos e o ELISAC e o PF são os mais promissores testes confirmatórios nessa espécie, já que ganhos adicionais de especificidade podem ser alcançados pelo aumento do ponto de corte. Tese (Doutorado).
American Journal of Veterinary Research
Chorioallantoic membrane (CAM) explants were used to determine the in vitro growth and cytotoxic ... more Chorioallantoic membrane (CAM) explants were used to determine the in vitro growth and cytotoxic potential of 3 strains of Brucella abortus. Bovine CAM explants were inoculated with 2 x 10(7) colony-forming units of the pathogenic strain 2308, attenuated strain 19, or the rough strain RB51 of B abortus. After inoculation, the explants were harvested and examined at 2 or 4 hours, 12 or 14 hours, and 24 or 26 hours of incubation. Bacterial growth associated with each explant was determined by counting colony-forming units. The degree of cellular damage in each explant associated either with bacterial growth or bacterial toxins was evaluated by morphometric analysis after trypan blue staining. Significant differences were not detected in the numbers of bacteria of any strain of B abortus in the CAM explants at comparable time intervals. The rate of growth of the bacteria in CAM explants was higher between 2 and 12 hours after inoculation than between 12 and 24 hours after inoculation. Cytotoxic effects associated with strain 2308 were significantly (P less than 0.05) greater than that caused by other strains. Cytotoxic effects associated with strain 19 and rough strain RB51 were similar, and both were significantly (P less than 0.05) greater than the phosphate buffer solution control. Chorioallantoic membrane explants inoculated with a filtrate of heat-killed strain 2308 induced minimal cellular damage, compared with that caused by the viable bacteria. These results indicated that the number of B abortus in trophoblasts was independent of the degree of cellular damage.
Revista Argentina de microbiología
Brucella abortus es una bacteria que causa abortos e infertilidad en el ganado y fiebre ondulante... more Brucella abortus es una bacteria que causa abortos e infertilidad en el ganado y fiebre ondulante en el hombre. Se multiplica en el citoplasma celular evadiendo los mecanismos de muerte intracelular. El óxido nítrico (NO) es importante en la regulación de la respuesta inmune. En el presente trabajo estudiamos la habilidad de tres cepas de B. abortus para sobrevivir intracelularmente en dos líneas celulares de macrófagos. La multiplicación de bacterias en ambas líneas celulares fue determinada a distintos tiempos en número de UFC/ml, también fue observada al microscopio de campo claro y de fluorescencia utilizando Giemsa y naranja de acridina, respectivamente. La tinción de ambas líneas celulares inoculadas con B. abortus mostró un resultado concordante con el encontrado en la determinación del número de UFC. Fue confirmada la presencia de B. abortus por microscopía electrónica. Para medir la producción de NO se utilizó el reactivo de Griess. La multiplicación de la cepa rugosa RB51 disminuyó en ambas líneas celulares y los niveles de NO fueron mayores en células inoculadas con dicha cepa que cuando fueron inoculadas con las cepas lisas (S19 y 2308). Estos resultados sugieren que probablemente la ausencia de cadena O en el lipopolisacárido afecta el crecimiento intracelular de B. abortus.
Revista Argentina de microbiología, 1999
Genome Mapping and Genomics in Animal-Associated Microbes, 2009
Brucellosis affects millions of animals and humans world-wide; in humans, over 500,000 new cases ... more Brucellosis affects millions of animals and humans world-wide; in humans, over 500,000 new cases are reported annually. Although some vaccines are available for its prevention in animals, none exist for humans. The causative agent is the facultative intracellular bacterial pathogen belonging to the genus Brucella and is transmitted from animals to humans; infected animals experience abortion and humans undulant fever.
Comparative Immunology, Microbiology and Infectious Diseases, 1993
Bovine brucellosis is a major disease of cattle characterized by abortion during the last trimest... more Bovine brucellosis is a major disease of cattle characterized by abortion during the last trimester of gestation. During many years important pieces of research have been done looking for a better understanding of this particular phenomenon. Yet, the fact that the abortion takes place in the last period of gestation result in a fascinating interrogant for such a unique event. The present review includes most of the information available regarding to this matter. Emphasis is done in the interaction of Brucella abortus with the trophoblastic cells of the bovine placenta.
Comparative Immunology, Microbiology and Infectious Diseases, 1996
The ability of Brucella to infect and grow within extraplacentomal chorioallantoic explants (CAMs... more The ability of Brucella to infect and grow within extraplacentomal chorioallantoic explants (CAMs) derived from early and late gestational cattle was compared. Following inoculation of CAMs with equal numbers of strain 2308 B. abortus, the infectivity was approximately the same in CAMs from both ages, however, bacterial replication was significantly greater in late gestational CAMs than in early gestational CAMs. Co-culture of both early and late gestation CAMs or culture of both types of CAMs in the presence of tissue culture media collected from either early or late B. abortus inoculated CAMs failed to alter B. abortus growth rates and/or cytopathic effects.
FEMS Immunology & Medical Microbiology, 2006
Although several outbreaks of Brucella melitensis infection have been reported among laboratory w... more Although several outbreaks of Brucella melitensis infection have been reported among laboratory workers or goat cheese consumers, outbreaks related to rural labour have been rarely studied. An outbreak of human brucellosis among farm workers of Argentina was studied and revealed a close relationship with an epidemic of caprine abortions which occurred shortly before on the same farm. High rates of B. melitensis infection were found among goats. Active brucellosis was diagnosed in 33 subjects (14 with positive blood culture for B. melitensis), while other 27 did not show evidence of illness. While 25 of the brucellosis active patients were rural workers, only 5 of the healthy subjects were engaged in rural labour. Active brucellosis was diagnosed in 91.3% of the subjects in continuous contact with goats and in 32% of those having an occasional contact with the animals. All the 60 subjects denied consumption of goat cheese or milk. As shown here, epidemic human infections by B. melitensis may develop among people frequently in contact with infected goat herds or goat manure. z 1998 Federation of European Microbiological Societies. Published by Elsevier Science B.V.
Avances En Ciencias Veterinarias, 1996
... Autor : Daffner S, Jose; Abalos P, Pedro; Scortti P, Mariela; Pinochet V, Lautaro; Samartino,... more ... Autor : Daffner S, Jose; Abalos P, Pedro; Scortti P, Mariela; Pinochet V, Lautaro; Samartino, Luis. ... mejores CDV que ofrecio fueron 90,2% para el grupo A. Mientras que en grupo B al Dia 45 brindo 86,7% de CDV, al Dia 90 alcanzo 90,0% y al Dia 180 su maximo rendimiento 95 ...
Fems Immunol Med Microbiol, 2006
Although several outbreaks of Brucella melitensis infection have been reported among laboratory w... more Although several outbreaks of Brucella melitensis infection have been reported among laboratory workers or goat cheese consumers, outbreaks related to rural labour have been rarely studied. An outbreak of human brucellosis among farm workers of Argentina was studied and revealed a close relationship with an epidemic of caprine abortions which occurred shortly before on the same farm. High rates of B. melitensis infection were found among goats. Active brucellosis was diagnosed in 33 subjects (14 with positive blood culture for B. melitensis), while other 27 did not show evidence of illness. While 25 of the brucellosis active patients were rural workers, only 5 of the healthy subjects were engaged in rural labour. Active brucellosis was diagnosed in 91.3% of the subjects in continuous contact with goats and in 32% of those having an occasional contact with the animals. All the 60 subjects denied consumption of goat cheese or milk. As shown here, epidemic human infections by B. melitensis may develop among people frequently in contact with infected goat herds or goat manure. z 1998 Federation of European Microbiological Societies. Published by Elsevier Science B.V.
Anuario De Investigacion Usal, Sep 24, 2014
Revista Argentina de microbiología
Brucella abortus is the causative agent of bovine brucellosis, a worldwide zoonosis. Up to date, ... more Brucella abortus is the causative agent of bovine brucellosis, a worldwide zoonosis. Up to date, eight biovars of B. abortus have been described. In Argentina, biovar 1 is the most frequently isolated. However, biovar 2, which is more pathogenic than biovar 1, is also found. Molecular methods for subtyping isolates are necessary for allowing epidemiological surveillance and control of eradication programs. Due to the genetic homogeneity of the genus Brucella, the development of molecular typing tools has been difficult. The publication of microorganism genomes facilitates the design of this approach. The aim of this work was to employ a Multiple Locus VNTR Analysis (MLVA) scheme for strains from Argentina isolated in our laboratory. From the 56 isolates analyzed, 47 different genotypic profiles were obtained. All the strains typed as biovar 2 showed the same profile. This scheme allowed assigning each isolate to the biovar it belongs to. All the genotypes were related using the goeBURST analysis and biovar 2 was proposed as founder.
American Journal of Veterinary Research
To determine shedding and colonization profiles in mature sexually intact bulls and pregnant heif... more To determine shedding and colonization profiles in mature sexually intact bulls and pregnant heifers after vaccination with a standard calfhood dose of Brucella abortus strain RB51 (SRB51). 6 sexually mature 3-year-old Jersey bulls and 7 mixed-breed heifers in midgestation. Bulls and pregnant heifers were vaccinated IM with the standard calfhood dose of 3x10(10) colony-forming units of SRB51. After vaccination, selected body fluids were monitored weekly for vaccine organism shedding. Pathogenesis was monitored in bulls by weekly breeding soundness examination and, in heifers, by delivery status of the calf. Vaccine organism colonization was assessed by obtaining select tissues at necropsy for bacterial culture. Serologic analysis was performed by use of numerous tests, including complement fixation, an SRB51-based ELISA, and immunoblot analysis. After vaccination, none of the vaccinated bulls or heifers shed SRB51 in their secretions. Results of breeding soundness examination for bulls were normal as was delivery status of the pregnant heifers (6 live births, 1 dystocia). At necropsy, SRB51 was not recovered from any of the selected tissues obtained from bulls, heifers, or calves; however, serologic analysis did detect SRB51-specific antibodies in all cattle. Vaccination with the standard calfhood dose of SRB51 administered IM was not associated with shedding or colonization in sexually mature bulls or pregnant heifers. Also, under conditions of this study with small numbers of animals, IM vaccination with SRB51 does not appear to cause any reproductive problems when administered to sexually mature cattle.
La leptospirosis es la zoonosis de mayor difusión en el mundo. Afecta a los animales dom ésticos ... more La leptospirosis es la zoonosis de mayor difusión en el mundo. Afecta a los animales dom ésticos y salvajes. El agente causal es una bacteria espiralada de forma y movimient o característicos, perteneciente al género Leptospira. Los portadores de mayor importancia son los roedores, los porcinos y los caninos, los cuales juegan un papel importante en la cadena epidemiológica. La penetración por la piel intacta o erosionada y por las mucosas constituye la forma más importante de adquirir la enfermedad. Para su aislamiento se procesan riñón, h ígado, bazo, pulm ón, glándula adrenal, m édula ósea y fluidos OBJETIVOS El objetivo de nuestro trabajo fue investigar si la leptospira es capaz de colonizar las glándulas salivales de cobayo. MATERIALES Y METODOS Los animales de laboratorio utilizados para este estudio fueron cobayos de 250 gramos. Se trabajó con tres cobayos, quienes fueron evaluados previamente mediante la técnica de MAT, resultando negativos. Se inoculó una cepa pat ógena ais...
Revista Argentina de microbiología
ABSTRACT Tendo em vista a importância da bubalinocultura como fonte de proteína para o Brasil e t... more ABSTRACT Tendo em vista a importância da bubalinocultura como fonte de proteína para o Brasil e também do Programa Nacional de Controle e Erradicação da Brucelose e da Tuberculose para a evolução das cadeias produtoras de bovinos e bubalinos e, devido à escassez de estudos sobre o sorodiagnóstico da brucelose na espécie bubalina, procedimento no qual se apóia o processo de certificação de rebanhos livres e monitorados, o presente estudo objetivou comparar o desempenho de diferentes testes para o sorodiagnóstico da brucelose nessa espécie. Soros de 696 fêmeas bubalinas adultas foram submetidos aos testes qualitativos BPA, AATE, AAT e quantitativos: SRP, SLT, ELISAI, ELISAC, PF e ME e FC. Foi empregada, gold standard, a combinação de dois testes, FC e ME, considerando dois critérios: a) animais positivos para os reagentes na FC (título=20UI) e no ME (critério para fêmea vacinada) e como negativos os animais não reagentes na FC (título<20UI) e no ME; b) animais positivos os reagentes na FC (título=20UI) e no ME (critério para fêmea não vacinada) e negativos os não reagentes na FC (título<20UI) e no ME. Esta consideração foi necessária em função dos animais não apresentarem histórico de vacinação confiável o que interfere na determinação do ponto de corte a ser utilizado no teste ME de animais vacinados e não vacinados. Desta forma, numa primeira análise todos os animais foram avaliados no ME como vacinados e em outra como não vacinados. C. (Continuação) inferidos para bubalinos com razoável segurança; b) devem ser estabelecidos pontos de corte específicos para búfalos para o SLT, o SRP e o ELISAI; c) as melhores combinações de sensibilidade e especificidade relativas foram alcançadas pelo ELISAC, o PF, o BPA e o AAT; d) os melhores resultados de Kappa foram verificados para o ELISAC (kappa), PF, BPA, AATE e AAT; e) o BPA, AAT e AATE são os melhores testes para o sorodiagnóstico de triagem em bubalinos e o ELISAC e o PF são os mais promissores testes confirmatórios nessa espécie, já que ganhos adicionais de especificidade podem ser alcançados pelo aumento do ponto de corte. Tese (Doutorado).
American Journal of Veterinary Research
Chorioallantoic membrane (CAM) explants were used to determine the in vitro growth and cytotoxic ... more Chorioallantoic membrane (CAM) explants were used to determine the in vitro growth and cytotoxic potential of 3 strains of Brucella abortus. Bovine CAM explants were inoculated with 2 x 10(7) colony-forming units of the pathogenic strain 2308, attenuated strain 19, or the rough strain RB51 of B abortus. After inoculation, the explants were harvested and examined at 2 or 4 hours, 12 or 14 hours, and 24 or 26 hours of incubation. Bacterial growth associated with each explant was determined by counting colony-forming units. The degree of cellular damage in each explant associated either with bacterial growth or bacterial toxins was evaluated by morphometric analysis after trypan blue staining. Significant differences were not detected in the numbers of bacteria of any strain of B abortus in the CAM explants at comparable time intervals. The rate of growth of the bacteria in CAM explants was higher between 2 and 12 hours after inoculation than between 12 and 24 hours after inoculation. Cytotoxic effects associated with strain 2308 were significantly (P less than 0.05) greater than that caused by other strains. Cytotoxic effects associated with strain 19 and rough strain RB51 were similar, and both were significantly (P less than 0.05) greater than the phosphate buffer solution control. Chorioallantoic membrane explants inoculated with a filtrate of heat-killed strain 2308 induced minimal cellular damage, compared with that caused by the viable bacteria. These results indicated that the number of B abortus in trophoblasts was independent of the degree of cellular damage.
Revista Argentina de microbiología
Brucella abortus es una bacteria que causa abortos e infertilidad en el ganado y fiebre ondulante... more Brucella abortus es una bacteria que causa abortos e infertilidad en el ganado y fiebre ondulante en el hombre. Se multiplica en el citoplasma celular evadiendo los mecanismos de muerte intracelular. El óxido nítrico (NO) es importante en la regulación de la respuesta inmune. En el presente trabajo estudiamos la habilidad de tres cepas de B. abortus para sobrevivir intracelularmente en dos líneas celulares de macrófagos. La multiplicación de bacterias en ambas líneas celulares fue determinada a distintos tiempos en número de UFC/ml, también fue observada al microscopio de campo claro y de fluorescencia utilizando Giemsa y naranja de acridina, respectivamente. La tinción de ambas líneas celulares inoculadas con B. abortus mostró un resultado concordante con el encontrado en la determinación del número de UFC. Fue confirmada la presencia de B. abortus por microscopía electrónica. Para medir la producción de NO se utilizó el reactivo de Griess. La multiplicación de la cepa rugosa RB51 disminuyó en ambas líneas celulares y los niveles de NO fueron mayores en células inoculadas con dicha cepa que cuando fueron inoculadas con las cepas lisas (S19 y 2308). Estos resultados sugieren que probablemente la ausencia de cadena O en el lipopolisacárido afecta el crecimiento intracelular de B. abortus.
Revista Argentina de microbiología, 1999
Genome Mapping and Genomics in Animal-Associated Microbes, 2009
Brucellosis affects millions of animals and humans world-wide; in humans, over 500,000 new cases ... more Brucellosis affects millions of animals and humans world-wide; in humans, over 500,000 new cases are reported annually. Although some vaccines are available for its prevention in animals, none exist for humans. The causative agent is the facultative intracellular bacterial pathogen belonging to the genus Brucella and is transmitted from animals to humans; infected animals experience abortion and humans undulant fever.
Comparative Immunology, Microbiology and Infectious Diseases, 1993
Bovine brucellosis is a major disease of cattle characterized by abortion during the last trimest... more Bovine brucellosis is a major disease of cattle characterized by abortion during the last trimester of gestation. During many years important pieces of research have been done looking for a better understanding of this particular phenomenon. Yet, the fact that the abortion takes place in the last period of gestation result in a fascinating interrogant for such a unique event. The present review includes most of the information available regarding to this matter. Emphasis is done in the interaction of Brucella abortus with the trophoblastic cells of the bovine placenta.
Comparative Immunology, Microbiology and Infectious Diseases, 1996
The ability of Brucella to infect and grow within extraplacentomal chorioallantoic explants (CAMs... more The ability of Brucella to infect and grow within extraplacentomal chorioallantoic explants (CAMs) derived from early and late gestational cattle was compared. Following inoculation of CAMs with equal numbers of strain 2308 B. abortus, the infectivity was approximately the same in CAMs from both ages, however, bacterial replication was significantly greater in late gestational CAMs than in early gestational CAMs. Co-culture of both early and late gestation CAMs or culture of both types of CAMs in the presence of tissue culture media collected from either early or late B. abortus inoculated CAMs failed to alter B. abortus growth rates and/or cytopathic effects.
FEMS Immunology & Medical Microbiology, 2006
Although several outbreaks of Brucella melitensis infection have been reported among laboratory w... more Although several outbreaks of Brucella melitensis infection have been reported among laboratory workers or goat cheese consumers, outbreaks related to rural labour have been rarely studied. An outbreak of human brucellosis among farm workers of Argentina was studied and revealed a close relationship with an epidemic of caprine abortions which occurred shortly before on the same farm. High rates of B. melitensis infection were found among goats. Active brucellosis was diagnosed in 33 subjects (14 with positive blood culture for B. melitensis), while other 27 did not show evidence of illness. While 25 of the brucellosis active patients were rural workers, only 5 of the healthy subjects were engaged in rural labour. Active brucellosis was diagnosed in 91.3% of the subjects in continuous contact with goats and in 32% of those having an occasional contact with the animals. All the 60 subjects denied consumption of goat cheese or milk. As shown here, epidemic human infections by B. melitensis may develop among people frequently in contact with infected goat herds or goat manure. z 1998 Federation of European Microbiological Societies. Published by Elsevier Science B.V.
Avances En Ciencias Veterinarias, 1996
... Autor : Daffner S, Jose; Abalos P, Pedro; Scortti P, Mariela; Pinochet V, Lautaro; Samartino,... more ... Autor : Daffner S, Jose; Abalos P, Pedro; Scortti P, Mariela; Pinochet V, Lautaro; Samartino, Luis. ... mejores CDV que ofrecio fueron 90,2% para el grupo A. Mientras que en grupo B al Dia 45 brindo 86,7% de CDV, al Dia 90 alcanzo 90,0% y al Dia 180 su maximo rendimiento 95 ...
Fems Immunol Med Microbiol, 2006
Although several outbreaks of Brucella melitensis infection have been reported among laboratory w... more Although several outbreaks of Brucella melitensis infection have been reported among laboratory workers or goat cheese consumers, outbreaks related to rural labour have been rarely studied. An outbreak of human brucellosis among farm workers of Argentina was studied and revealed a close relationship with an epidemic of caprine abortions which occurred shortly before on the same farm. High rates of B. melitensis infection were found among goats. Active brucellosis was diagnosed in 33 subjects (14 with positive blood culture for B. melitensis), while other 27 did not show evidence of illness. While 25 of the brucellosis active patients were rural workers, only 5 of the healthy subjects were engaged in rural labour. Active brucellosis was diagnosed in 91.3% of the subjects in continuous contact with goats and in 32% of those having an occasional contact with the animals. All the 60 subjects denied consumption of goat cheese or milk. As shown here, epidemic human infections by B. melitensis may develop among people frequently in contact with infected goat herds or goat manure. z 1998 Federation of European Microbiological Societies. Published by Elsevier Science B.V.
Anuario De Investigacion Usal, Sep 24, 2014
Revista Argentina de microbiología
Brucella abortus is the causative agent of bovine brucellosis, a worldwide zoonosis. Up to date, ... more Brucella abortus is the causative agent of bovine brucellosis, a worldwide zoonosis. Up to date, eight biovars of B. abortus have been described. In Argentina, biovar 1 is the most frequently isolated. However, biovar 2, which is more pathogenic than biovar 1, is also found. Molecular methods for subtyping isolates are necessary for allowing epidemiological surveillance and control of eradication programs. Due to the genetic homogeneity of the genus Brucella, the development of molecular typing tools has been difficult. The publication of microorganism genomes facilitates the design of this approach. The aim of this work was to employ a Multiple Locus VNTR Analysis (MLVA) scheme for strains from Argentina isolated in our laboratory. From the 56 isolates analyzed, 47 different genotypic profiles were obtained. All the strains typed as biovar 2 showed the same profile. This scheme allowed assigning each isolate to the biovar it belongs to. All the genotypes were related using the goeBURST analysis and biovar 2 was proposed as founder.
American Journal of Veterinary Research
To determine shedding and colonization profiles in mature sexually intact bulls and pregnant heif... more To determine shedding and colonization profiles in mature sexually intact bulls and pregnant heifers after vaccination with a standard calfhood dose of Brucella abortus strain RB51 (SRB51). 6 sexually mature 3-year-old Jersey bulls and 7 mixed-breed heifers in midgestation. Bulls and pregnant heifers were vaccinated IM with the standard calfhood dose of 3x10(10) colony-forming units of SRB51. After vaccination, selected body fluids were monitored weekly for vaccine organism shedding. Pathogenesis was monitored in bulls by weekly breeding soundness examination and, in heifers, by delivery status of the calf. Vaccine organism colonization was assessed by obtaining select tissues at necropsy for bacterial culture. Serologic analysis was performed by use of numerous tests, including complement fixation, an SRB51-based ELISA, and immunoblot analysis. After vaccination, none of the vaccinated bulls or heifers shed SRB51 in their secretions. Results of breeding soundness examination for bulls were normal as was delivery status of the pregnant heifers (6 live births, 1 dystocia). At necropsy, SRB51 was not recovered from any of the selected tissues obtained from bulls, heifers, or calves; however, serologic analysis did detect SRB51-specific antibodies in all cattle. Vaccination with the standard calfhood dose of SRB51 administered IM was not associated with shedding or colonization in sexually mature bulls or pregnant heifers. Also, under conditions of this study with small numbers of animals, IM vaccination with SRB51 does not appear to cause any reproductive problems when administered to sexually mature cattle.
La leptospirosis es la zoonosis de mayor difusión en el mundo. Afecta a los animales dom ésticos ... more La leptospirosis es la zoonosis de mayor difusión en el mundo. Afecta a los animales dom ésticos y salvajes. El agente causal es una bacteria espiralada de forma y movimient o característicos, perteneciente al género Leptospira. Los portadores de mayor importancia son los roedores, los porcinos y los caninos, los cuales juegan un papel importante en la cadena epidemiológica. La penetración por la piel intacta o erosionada y por las mucosas constituye la forma más importante de adquirir la enfermedad. Para su aislamiento se procesan riñón, h ígado, bazo, pulm ón, glándula adrenal, m édula ósea y fluidos OBJETIVOS El objetivo de nuestro trabajo fue investigar si la leptospira es capaz de colonizar las glándulas salivales de cobayo. MATERIALES Y METODOS Los animales de laboratorio utilizados para este estudio fueron cobayos de 250 gramos. Se trabajó con tres cobayos, quienes fueron evaluados previamente mediante la técnica de MAT, resultando negativos. Se inoculó una cepa pat ógena ais...
Revista Argentina de microbiología