Characterization of Staphylococcus intermedius from pigeons, dogs, foxes, mink, and horses by pulsed-field gel electrophoresis.

Staphylococcus intermedius from pigeons, dogs, foxes, mink, and horses, was characterized by pulsed-field gel electrophoresis (PFGE) to evaluate the use of this typing method for discriminating among strains. SmaI cut the chromosomal DNA into 7-13 fragments ranging from approximately 48 kb to 655 kb, with most of the detectable fragments being smaller than 172 kb. S. intermedius from various animals had a high degree of restriction fragment length polymorphism. Pigeon strains have a similar genotype, despite the difference in their isolation area. Phage typing indicated that the dog, fox, and mink strains belong to the canine I or canine II type. The PFGE method further differentiated the mink strains from the dog and fox strains with regard to three fragments between 256 kb and 570 kb. As such, genomic DNA fingerprinting by PFGE appears to be an effective technique for discriminating S. intermedius strains from various animals. A combination of PFGE typing and phage typing would provide more detailed information than the single method for ecological investigations of S. intermedius.