Population structure and diversity of avian isolates of Pasteurella multocida from Australia.

A total of 110 isolates of Pasteurella multocida from Australian poultry and reference strains for the 16 somatic serovars plus the three subspecies (gallicida, multocida, septica) were analysed to examine their population structure and diversity. The 81 field isolates examined by multilocus enzyme electrophoresis (MLEE) were diverse, being divided into 56 electrophoretic types (ETs), with the 19 reference strains in another 15 ETs. The population was clonal and somatic serotyping was not particularly useful in establishing relationships between isolates.