Pheno- and genotypic characteristics of Pasteurella multocida avian isolates in selected provinces of Iran

Poultry pasteurellosis affected domestic and wildbirds all over the world. Present study was designed in order to isolation and survey of pheno- and genotypic characteristics of Pasteurella multocida bacterium isolated from chickens, turkeys, geese and ducks in different areas of Mazandaran, Guilan, East-Azarbaijan and Khoozestan provinces. After the collection of 701 tracheal swab samples, 12 (1.7%) strains of P. multocida were isolated based on cultural methods; then 7 (0.99%) isolates were confirmed by application of specific primers of kmt1. Biotyping tests showed that all isolates are owned by P. multocida subspecies multocida. Based on the results of capsular typing and detection of virulence factors of the isolates using specific primers, 5 (71.4%) isolates were identified as P. multocida serotype A and 2 (28.5%) isolates were untypeable. Also, the tests showed that the sodC, hgbA, hgbB, nanB,nanH and ptfA genes and ompH, oma87, exBD-tonB, and pfhA genes were present in 71.4% and 57.1% of the isolates, respectively and toxA and sodA genes were not identified in any of the studied isolates. According to the results of determination of the drug -resistance patterns of the isolates by disk diffusion method, all isolates (100%) were sensitive to cephalexin, flumequine, florfenicol, trimethoprim-sulfamethoxazole, sultrim and fosfomycin but were resistant to cloxacillin. The results of this research showed alow prevalence of P. multocida among under investigation poultry in the understudy geographic area (P