INVESTIGATE OF VIRULENCE- GENES OF PASTEURELLA MULTOCIDA TYPES AND ANTIBIOTIC SUSCEPTIBILITY IN BUFFALOES IN MARSHES OF SOUTH OF IRAQ

Abstract

This study was conducted to investigate the incidence of Pasteurella multocida in buffaloes in south of Iraq. A total 393 of different ages and sexes, were clinically examined. Nasal swabs and blood samples were taken .  Enrich and Selective medias  ,biochemical tests and Gram stain were used. also used  antibiotic susceptibility. All positive cases confirmed by polymerase chain reaction with specific primer to P. multocida  then use specific  primers to detect P.multocida A,B. Also use specific primers to detect some virulence gene (pfhA ; nanH ; ompA ; hgbA) .Prevalence of P. multocida types in marshes area which it appear   35 samples 35% to type A and it significant variation at (P≤0.05) than types  (B) which found 65 samples 65 %  also it significant variation. Capsular typing of 100 isolates in marshes appeared  35 (35%) to type A , 65 (65 %)  to type B with significantly variation between types  . Distribution of virulence- genes appeared   75 (75%) to ompA , hgbA 59 (59 %)  , nanH 46 ( 46 %)  and pfhA 33(33%) with significantly variation between genes  .No significant  variation of prevalence of virulence- genes between infected and non-infected. Also prevalence of Pasteurella multocida virulence- genes which it appear   49(74.2%);26(76.4%)to ompA , 41(62.1), 18(52.9) to hgbA ; 27(40.9), 19(55.9) to nanH and 20(30,3) ,13(38.3) to pfhA for diseased and non diseased respectively .Prevalence of P.multocida virulence- genes appeared   25(71.4); 50(76.9); to ompA , 18(51.4), 41(63.1); to hgbA ; 16(45), 30(47.6) to nanh and 16(45.7) , 17(27.0); to pfhA for type A and type B respectively.

The antibiotics susceptibility of 52 isolated which from 25 type B , 25 type A and showed that : Cefotaxime , Cefitrixone, Azithromycin and Tilmicosin  founded 100% susceptibility ,followed by Chloromphinocol as 96-92%, Tetracycline 40-32% while Ampicilline32-28 %.

Conclusions of present study are : P. multocida endemic in buffaloes in south of Iraq. Recoded of virulence genes of P. multocida in buffaloes in Iraq. Cefotaxime , Cefitrixone, Azithromycin and Tilmicosin are the best choice to treatment. PCR assay  is best technique  to diagnosis and detect.