Molecular characterization of field isolates of Pasteurella multocida by polymerase chain reaction in the state of Haryana

The studies involved Pasteurella multocida isolated from animals affected with haemorrhagic septicaemia in Haryana, India, during 2006 and 2007. The disease was initially diagnosed by clinical symptoms and mortality pattern. A total of 12 isolates from different outbreaks during this period, were isolated and confirmed by conventional methods like cultural, biochemical methods and finally by molecular techniques by Pasteurella multocida species-specific PCR assay (PM-PCR), PCR assay for HS- associated type B serotypes of P. multocida (HSB-PCR) and multiplex PCR. None of these twelve Pasteurella multocida isolates could be differentiated on the basis of cultural and biochemical characters, and pathogenicity. The PCR assay applied on direct bacterial colony and boiled culture using specific primers gave an amplified product 460 bp specific for P. multocida and 620 bp specific for P. multocida serotype B:2. The multiplex PCR could identify the species as well as the serotype of P. multocida in the same reaction. The PCR techniques were found to provide rapid and accurate diagnosis of P. multocida isolates from cattle and buffalo during the investigation of suspected haemorrhagic septicaemia outbreaks.