GENOMIC FINGERPRINTING OF HAEMOPHILUS-SOMNUS BY A COMBINATION OF PCR METHODS

Twenty-three isolates of Haemophilus somnus were typed by repetitive e xtragenic palindromic (REP) element-based PCR, enterobacterial repetit ive intergenic consensus (ERIC)-based PCR, and PCR ribotyping. A total of 11 types were distinguished by REP-PCR, 13 types were distinguishe d by ERIC-PCR, and 5 types were distinguished by PCR ribotyping. PCR r ibotyping produced a relatively simple pattern and a small number of d istinct types, whereas REP- and ERIC-PCR both produced more complex ba nding patterns but increased the discrimination between strains. Clear ly distinguishable profiles were obtained for respiratory and genital isolates of H. somnus by all three typing methods. The results suggest that a combination of all three primer sets provides a high-resolutio n fingerprinting method for epidemiological studies of H. somnus and f or its differentiation from related species.