Molecular characterisation of avian Pasteurella multocida isolates from Australia and Vietnam by REP-PCR and PFGE

A total of 95 isolates of Pasteurella multocida were analysed by pulsed fie ld gel electrophoresis (PFGE) using the enzyme ApaI, including 73 avian iso lates from Australia and 22 from Vietnam. The majority of field isolates we re capsular Type A, with the predominant somatic serovars of 1, 3, 4 and 3, 4. Twenty-one distinct profiles were evident among the Australian isolates, with only 3 profiles observed among the 22 P. multocida strains isolated f rom Vietnam. Within the Australian isolates, related and unrelated outbreak s could be identified by PFGE. These results correlated well with previousl y published studies, with greater discrimination shown by PFGE, Repetitive extragenic palindromic sequence PCR (REP-PCR) analysis of representative is olates from PFGE classifications yielded 21 profiles, with most of the subg roups in accordance with PFGE analysis. While REP-PCR was shown to be less discriminating than PFGE, the epidemiological relatedness of strains compar ed favourably between the techniques. Thus, the ease and rapidity of REP-PC R while maintaining a high level of differentiation, supports the use of RE P-PCR as a competent alternative to the more labour-intensive PFGE system f or strain identification and epidemiological studies of avian P. multocida. (C) 2000 Elsevier Science B.V. All rights reserved.