Typing of Treponema hyodysenteriae by restriction endonuclease analysis.

Restriction endonuclease analysis (REA) was used to type eight well-characterised strains of Treponema hyodysenteriae originating from the U.K., Canada and the U.S.A., and 16 isolates from cases of swine dysentery in Western Australia (W.A.). Several of the W.A. isolates were also serotyped by the method of Baum and Joens (1979), and the two typing techniques were compared. REA typing was more discriminatory than serotyping, being able to distinguish strains within serotypes. The new technique was neither more difficult nor more time-consuming to perform than serotyping. Within the 16 W.A. isolates, three different REA patterns were identified, with common patterns found on different farms. The eight overseas strains had seven different REA patterns, all of which could be distinguished from the patterns of the W.A. isolates.