Molecular typing techniques have been used to determine the extent of strain variation in Serpulina hyodysenteriae, and have been useful in studying the molecular epidemiology of swine dysentery (SD). Techniques used have included multilocus enzyme electrophoresis (MEE) (6), DNA restriction endonuclease analysis (REA) (3), restriction fragment length polymorphism (RFLP) analysis (5), and random amplification of polymorphic DNA (RAPD) analysis (4). In the current study, pulsed field gel electrophoresis (PFGE) was developed as a simple and reliable alternative method for subspecific differentiation of the species
