A rapid pulsed-field gel electrophoresis method of genotyping Haemophilus parasuis isolates

Abstract

To develop a modified pulsed-field gel electrophoresis (PFGE) method for characterizing Haemophilus parasuis isolates. A modified PFGE procedure was designed using CpoI to generate restriction maps of H. parasuis genomic DNA. This approach was used to characterize 47 H. parasuis clinical isolates and 15 reference strains. All strains could be typed by this method, and the procedure was completed in 36 h. A total of 39 different PFGE patterns were identified among 47 epidemiologically unrelated clinical isolates. The modified PGFE described in this report efficiently characterized H. parasuis isolates. This method can be adopted for studying the epidemiology of Glässer's disease outbreaks in addition to differentiating and classifying previously untypeable H. parasuis isolates. The modified PFGE method described is a novel means of characterizing H. parasuis isolates. It is also a highly discriminatory molecular typing method (discriminatory index of 0.98) that can overcome the limitations of serotyping.