RESUMO
The objectives of the study were to investigate the phenotypic and genotypic characterization of the persistent Salmonella Enteritidis (S. Enteritidis) isolates in two integrated broiler chicken operations, with attention focused mainly on the epidemiological approach. In the distribution of virulence genes, Salmonella enterotoxin (stn), invading host cell (invA), and Salmonella plasmid virulence (spvC) genes were widely distributed among the S. Enteritidis irrespective of their source of isolation, and Salmonella fimbrial (sefC) and plasmid encoded fimbrial (pef) genes were present in 28 and 20 S. Enteritidis strains, respectively. A total of 5 different XbaI-PFGE types were obtained from 31 S. Enteritidis isolates. Twenty-one types were divided on the basis their PFGE pattern, phage type and antimicrobial resistance pattern determined. There was a significant difference in phenotypic and genotypic characterization by two integrated broiler operations. Also, 8 isolates shown susceptible to all antimicrobials and 11 isolates with resistance to nalidixic acid were partly classified by XbaI PFGE pattern and by the phage type.
Assuntos
Galinhas , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Salmonella enteritidis/crescimento & desenvolvimento , Animais , Proteínas de Bactérias/genética , Tipagem de Bacteriófagos/veterinária , Análise por Conglomerados , DNA Bacteriano/genética , Eletroforese em Gel de Campo Pulsado/veterinária , Enterotoxinas/genética , Proteínas de Fímbrias/genética , Coreia (Geográfico)/epidemiologia , Testes de Sensibilidade Microbiana/veterinária , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Doenças das Aves Domésticas/epidemiologia , Prevalência , Salmonelose Animal/epidemiologia , Salmonella enteritidis/genética , Salmonella enteritidis/isolamento & purificação , Salmonella enteritidis/patogenicidadeRESUMO
Controlling Salmonella in integrated broiler operation is complicated because there are numerous potential sources of Salmonella contamination, including chicks, feed, rodents, wild poultry operations, and the processing plant. The objective of this study was to investigate the distribution of Salmonella through all phases of two integrated broiler operations and to determine the key areas related to the control of all known sources of infection. Two different Salmonella serotypes were observed at integrated broiler chicken company A. S. enteritidis, the predominant company A isolate, was consistently found in the breeder farm, hatcheries, broiler farms, and chicken slaughterhouse. At company B, a total of six different serotypes, S. heidelberg, S. senftenberg, S. enteritidis, S. blockley, S. gallinarum, and S. virchow, were detected. Although S. heidelberg was not found in the broiler farms, it was consistently found in the breeder farm, hatcheries, and chicken slaughterhouse. In addition, S. enteritidis was found in the hatcheries, broiler farm, and chicken slaughterhouse. In order to obtain the genetic clonality, 22 S. enteritidis isolates were digested with XbaI and analyzed by pulsed-field gel electrohporesis (PFGE). A difference in the PFGE pattern was found to be related to the origin of the integrated broiler operation. These data support the critical need to control Salmonella in breeder farms and hatcheries, and demonstrate important points related to the control of infection in large-scale poultry operations of Korea.
