RESUMO
Enterotoxigenic Escherichia coli (ETEC) is the major pathogen responsible for neonatal diarrhea, postweaning diarrhea, and edema disease in pigs. Although it can be harmless, ETEC is also present in the intestines of other animal species and humans, causing occasional diarrhea outbreaks. The evaluation of this pathogen's presence in food sources is becoming an increasingly important issue in human health. In order to determine the prevalence of ETEC in nondiarrheic pigs, 990 animals from 11 pig farms were sampled. Using end-time polymerase chain reaction (PCR), eltA, estI genes, or both, were detected in 150 (15.2%) animals. From the positive samples, 40 (26.6%) ETEC strains were isolated, showing 19 antibiotic-resistance patterns; 52.5% of these strains had multiple antibiotic resistances, and 17.5% carried the intI2 gene. The most prevalent genotypes were rfb(O157)/estII/aidA (32.5%) and estI/estII (25.0%). The estII gene was identified most frequently (97.5%), followed by estI (37.5%), astA (20.0%), and eltA (12.5%). The genes coding the fimbriae F5, F6, and F18 were detected in three single isolates. The aidA gene was detected in 20 ETEC strains associated with the estII gene. Among the isolated ETEC strains, stx(2e)/estI, stx(2e)/estI/estII, and stx(2e)/estI/estII/intI2 genotypes were identified. The ETEC belonged to 12 different serogroups; 37.5% of them belonged to serotype O157:H19. Isolates were grouped by enterobacterial repetitive intergenic consensus-PCR into 5 clusters with 100.0% similarity. In this study, we demonstrated that numerous ETEC genotypes cohabit and circulate in swine populations without clinical manifestation of neonatal diarrhea, postweaning diarrhea, or edema disease in different production stages. The information generated is important not only for diagnostic and epidemiological purposes, but also for understanding the dynamics and ecology of ETEC in pigs in different production stages that can be potentially transmitted to humans from food animals.
Assuntos
Anti-Infecciosos/análise , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli Enterotoxigênica/isolamento & purificação , Genes Bacterianos , Carne Vermelha/microbiologia , Animais , Anti-Infecciosos/farmacologia , DNA Bacteriano/genética , Diarreia/microbiologia , Diarreia/veterinária , Edematose Suína/microbiologia , Escherichia coli Enterotoxigênica/efeitos dos fármacos , Escherichia coli Enterotoxigênica/genética , Proteínas de Escherichia coli/genética , Contaminação de Alimentos , Microbiologia de Alimentos , Técnicas de Genotipagem , Carne Vermelha/análise , Suínos , Doenças dos Suínos/microbiologiaRESUMO
The exotoxin SLT-IIeB from the Escherichia coli Ee strain was expressed in E. coli, and the recombinant protein was purified, mixed with the Ee strain, then emulsified with oil-emulsion adjuvants to obtain a mixed subunit bacterin. Groups of Kunming mice were immunized at weeks 0 and 2, and challenged intraperitoneally with the Ee strain at week 4. Antibodies were detected by ELISA and an agglutination test. After the second immunization, the antibody level increased and the rate of immune protection against the Ee strain was 70 and 91.7% in the subunit bacterin and bacterin groups, respectively. Therefore, the mixed subunit bacterin provided good protection against the homologous Ee strain, which provides a basis for further research, into high-efficacy vaccines against porcine edema disease.
Assuntos
Vacinas Bacterianas/administração & dosagem , Edematose Suína/genética , Infecções por Escherichia coli/genética , Toxina Shiga II/genética , Animais , Vacinas Bacterianas/genética , Edematose Suína/tratamento farmacológico , Edematose Suína/patologia , Ensaio de Imunoadsorção Enzimática , Escherichia coli/genética , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/patologia , Imunização , Camundongos , Subunidades Proteicas/genética , Toxina Shiga II/administração & dosagem , Suínos/microbiologiaRESUMO
The purpose of this work was to characterize 47 Escherichia coli strains isolated from 32 pigs diagnosed with postweaning diarrhea and three pigs with edema disease by PCR. Forty two (95.5 %) of the strains isolated from diarrheic pigs were characterized as enterotoxigenic E. coli (ETEC) and 2 (4.5 %) as Shiga toxin-producing E. coli (STEC). Fourteen (33.3 %) ETEC strains were positive for est/estII/fedA genes. The most complex genotype was eltA/estI/faeG/aidA. Strains isolated from pigs with ED were classified as porcine STEC and were stx2e/aidA carriers. Eleven (25 %) strains carried the gene encoding adhesin protein AIDA-I. However, genes coding for F5, F6, F41, intimin and Paa were not detected. The development of vaccines generating antibodies against prevalent E. coli adhesins in Argentina could be useful for the prevention of PWD and ED.
Assuntos
Diarreia/veterinária , Edematose Suína/microbiologia , Escherichia coli Enterotoxigênica/genética , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Genes Bacterianos , Escherichia coli Shiga Toxigênica/genética , Doenças dos Suínos/microbiologia , Adesinas de Escherichia coli/genética , Animais , Argentina/epidemiologia , Diarreia/epidemiologia , Diarreia/microbiologia , Surtos de Doenças , Edematose Suína/epidemiologia , Escherichia coli Enterotoxigênica/isolamento & purificação , Enterotoxinas/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Genótipo , Escherichia coli Shiga Toxigênica/isolamento & purificação , Sus scrofa , Suínos , Doenças dos Suínos/epidemiologia , DesmameRESUMO
El objetivo del trabajo fue caracterizar mediante PCR 47 aislamientos de Escheríchia coli recuperados de 32 cerdos con diagnóstico clínico de diarrea posdestete (DPD) y de 3 cerdos con enfermedad de los edemas (ED). Sobre 44 aislamientos provenientes de cerdos con DPD, 42 (95,5 %) fueron caracterizados como E. coli enterotoxigénicos (ETEC) y 2 (4,5 %) como E. coli productores de toxina Shiga (STEC). Catorce aislamientos de ETEC (33,3 %) fueron positivos para los genes estl/estlI/fedA. El genotipo más complejo fue eltA/estll/east1/faeG/aidA. Los aislamientos provenientes de cerdos con ED se clasificaron como STEC porcinos y fueron portadores de stxJaidA. Once aislamientos (25 %) fueron portadores del gen que codifica la expresión de la adhesina AIDA-I. Sin embargo, en ningún aislamiento se detectaron los genes que codifican la expresión de las adhesinas F5, F6, F41, de intimina y de "Paa". La prevención de la DPD y de la ED podría realizarse mediante el desarrollo de vacunas que generen anticuerpos contra las adhesinas de las cepas de E. coli prevalentes en la Argentina.
The purpose of this work was to characterize 47 Escherichia coli strains isolated from 32 pigs diagnosed with postweaning diarrhea and tree pigs with edema disease by PCR. Forty two (95.5 %) of the strains isolated from diarrheic pigs were characterized as enterotoxigenic E. coli (ETEC) and 2 (4.5 %) as Shiga toxin-producing E. coli (STEC). Fourteen (33.3 %) ETEC strains were positive for est/estll/fedA genes. The most complex genotype was eltA/estl/faeG/aidA. Strains isolated from pigs with ED were classified as porcine STEC and were stxjaidA carriers. Eleven (25 %) strains carried the gene encoding adhesln protein AIDA-I. However, genes coding for F5, F6, F41, intimin and Paa were not detected. The development of vaccines generating antibodies against prevalent E. coli adhesins in Argentina could be useful for the prevention of PWD and ED.
Assuntos
Animais , Diarreia/veterinária , Edematose Suína/microbiologia , Escherichia coli Enterotoxigênica/genética , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Genes Bacterianos , Escherichia coli Shiga Toxigênica/genética , Doenças dos Suínos/microbiologia , Adesinas de Escherichia coli/genética , Argentina/epidemiologia , Surtos de Doenças , Diarreia/epidemiologia , Diarreia/microbiologia , Edematose Suína/epidemiologia , Escherichia coli Enterotoxigênica/isolamento & purificação , Enterotoxinas/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Genótipo , Sus scrofa , Suínos , Escherichia coli Shiga Toxigênica/isolamento & purificação , Doenças dos Suínos/epidemiologia , DesmameRESUMO
El objetivo del trabajo fue caracterizar mediante PCR 47 aislamientos de Escheríchia coli recuperados de 32 cerdos con diagnóstico clínico de diarrea posdestete (DPD) y de 3 cerdos con enfermedad de los edemas (ED). Sobre 44 aislamientos provenientes de cerdos con DPD, 42 (95,5 %) fueron caracterizados como E. coli enterotoxigénicos (ETEC) y 2 (4,5 %) como E. coli productores de toxina Shiga (STEC). Catorce aislamientos de ETEC (33,3 %) fueron positivos para los genes estl/estlI/fedA. El genotipo más complejo fue eltA/estll/east1/faeG/aidA. Los aislamientos provenientes de cerdos con ED se clasificaron como STEC porcinos y fueron portadores de stxJaidA. Once aislamientos (25 %) fueron portadores del gen que codifica la expresión de la adhesina AIDA-I. Sin embargo, en ningún aislamiento se detectaron los genes que codifican la expresión de las adhesinas F5, F6, F41, de intimina y de "Paa". La prevención de la DPD y de la ED podría realizarse mediante el desarrollo de vacunas que generen anticuerpos contra las adhesinas de las cepas de E. coli prevalentes en la Argentina.(AU)
The purpose of this work was to characterize 47 Escherichia coli strains isolated from 32 pigs diagnosed with postweaning diarrhea and tree pigs with edema disease by PCR. Forty two (95.5 %) of the strains isolated from diarrheic pigs were characterized as enterotoxigenic E. coli (ETEC) and 2 (4.5 %) as Shiga toxin-producing E. coli (STEC). Fourteen (33.3 %) ETEC strains were positive for est/estll/fedA genes. The most complex genotype was eltA/estl/faeG/aidA. Strains isolated from pigs with ED were classified as porcine STEC and were stxjaidA carriers. Eleven (25 %) strains carried the gene encoding adhesln protein AIDA-I. However, genes coding for F5, F6, F41, intimin and Paa were not detected. The development of vaccines generating antibodies against prevalent E. coli adhesins in Argentina could be useful for the prevention of PWD and ED.(AU)
Assuntos
Animais , Diarreia/veterinária , Edematose Suína/microbiologia , Escherichia coli Enterotoxigênica/genética , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Genes Bacterianos , Escherichia coli Shiga Toxigênica/genética , Doenças dos Suínos/microbiologia , Adesinas de Escherichia coli/genética , Argentina/epidemiologia , Diarreia/epidemiologia , Diarreia/microbiologia , Surtos de Doenças , Edematose Suína/epidemiologia , Escherichia coli Enterotoxigênica/isolamento & purificação , Enterotoxinas/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Genótipo , Escherichia coli Shiga Toxigênica/isolamento & purificação , Sus scrofa , Suínos , Doenças dos Suínos/epidemiologia , DesmameRESUMO
La enfermedad edematica del cerdo es una afeccion aguda frecuente, con alteraciones desde la anorexia, indiferencia, diarrea, edema en parpados y cuello que cursa en los primeros meses de edad... (AU)
Assuntos
Animais , Edematose Suína/terapia , Doenças dos Suínos , Abelhas/uso terapêutico , Custos de Cuidados de SaúdeRESUMO
La enfermedad edematica del cerdo es una afeccion aguda frecuente, con alteraciones desde la anorexia, indiferencia, diarrea, edema en parpados y cuello que cursa en los primeros meses de edad...
Assuntos
Animais , Edematose Suína/terapia , Abelhas , Custos de Cuidados de Saúde , Doenças dos SuínosRESUMO
The objectives of the research were to determine the presence of the gene sequences for Shiga Toxin 2e (Stx2e), enterotoxins (ST-I, ST-II and LT-I), and F18 fimbriae in 144 Escherichia coli strains isolated from pigs with edema disease; to assess the ability of stx2e(+) strains to produce Stx2e; and to determine the O serogroups of the E. coli strains. Presence of the genes was determined by polymerase chain reaction (PCR), production of Stx2e was assessed by cytotoxicity for Vero and Hela cells, O serogroups were identified by agglutination with specific antisera. Of the 144 strains tested, 99 were stx2e(+) by PCR, but only 45 of these were Stx2e(+) in the cell culture assays. Among the 99 stx2e(+) strains, PCR detected the genes for F18ab, ST-I, ST-II, LT-I in 76, 40, 31 and 16 strains, respectively. Forty-one of the 99 sxt2e(+) strains belonged to O group 139; the rest did not belong to the classical edema disease O serogroups. It is likely that the enterotoxins, whose genes were detected at high frequency, are responsible for diarrhea seem in pigs with edema disease in Brazil.