Long-term prevalence of antimicrobial-resistant Salmonella enterica subspecies enterica Serovar infantis in the broiler chicken industry in Japan.
Eleven broiler isolates of Salmonella Infantis obtained between 1989 and 1998 were examined for antimicrobial susceptibility and pulse field gel electrophoresis (PFGE) profiles. Seven strains of S. Infantis isolated after 1993 harbored similar antimicrobial susceptibilities to the recent isolates between 2001 and 2003. In comparison of PFGE profile with 22 isolates obtained from 22 apparently healthy broiler chickens between 2001 and 2003, the predominant cluster included the seven strains isolated after 1993. We could not clarify the reasons why the serovar has been prevalent in the broiler industry for a long time, but current antimicrobial usage is not always linked to its prevalence.
Asai
Tetsuo
T
National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, Tokyo, Japan.
Ishihara
Kanako
K
Harada
Kazuki
K
Kojima
Akemi
A
Tamura
Yutaka
Y
Sato
Shizuo
S
Takahashi
Toshio
T
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002645:Chickens / Q000382:microbiology*; D016000:Cluster Analysis; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005516:Food Microbiology; D007564:Japan / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D011201:Poultry Diseases / Q000453:epidemiology / Q000382:microbiology*; D015995:Prevalence; D012481:Salmonella Infections, Animal / Q000453:epidemiology / Q000382:microbiology*; D019779:Salmonella enterica / Q000145:classification / Q000187:drug effects* / Q000302:isolation & purification*
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial