Genetic and phenotypic variability among Salmonella enterica serovar Typhimurium isolates from California dairy cattle and humans.
Fifty-six human and 24 adult dairy cattle isolates of Salmonella enterica serovar Typhimurium from a single county in California were compared using ribotyping, insertion sequence typing (IS200), pulsed-field gel electrophoresis, plasmid typing, phage typing, and antimicrobial resistance testing. The majority of the isolates fell into one of two groups which were phage types DT104 and DT193. Combining the information from all typing methods, a total of 45 different "clusters" were defined, with 35 of those including only a single isolate. The library of isolates had a high degree of variability, but antibiotic resistance and plasmid typing each defined single clusters in which human or bovine isolates predominated (chi2, P < 0.05).
Adaska
J M
JM
California Animal Health and Food Safety Laboratory, Tulare Branch, 18830 Road 112, Tulare, CA 93274, USA. jmadaska@ucdavis.edu
Silva
A J
AJ
Berge
A C B
AC
Sischo
W M
WM
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015373:Bacterial Typing Techniques; D001435:Bacteriophages / Q000235:genetics; D002140:California; D002417:Cattle; D024881:Drug Resistance, Bacterial / Q000502:physiology*; D016521:Electrophoresis, Gel, Pulsed-Field; D014644:Genetic Variation; D006801:Humans; D010957:Plasmids / Q000235:genetics; D021521:Ribotyping; D012480:Salmonella Infections / Q000382:microbiology; D019779:Salmonella enterica / Q000235:genetics; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification
D000900:Anti-Bacterial Agents