IDENTIFICATION OF TOX A GENE IN CUBAN ISOLATES OF Pasteurella multocida FROM SWINE USING THE POLYMERASE CHAIN REACTION (PCR)

Pasteurella multocida is part of the commensal flora in the upper respiratory tract of pigs. Usually, P. multocida type A strains are associated to pneumonia in grower pigs and the ones from serotype D encode for a 145 kDa toxin associated to progressive rhinitis. Thirty Pasteurella multocida strains isolated in Cuba from swine samples with respiratory signs were identified and characterized. All the isolates showed an amplification product of 460 pb when KMT1SP6 and KMT1T7 primers were used. Only four toxigenic strains of P. multocida were identified by PCR. These data presented revealed low frequency of toxigenic P.multocida and a higher incidence of non toxigenic P.multocida associated to pneumonie.The PCR specifically for identifing P.multocida and the specific primers for tox A gene have been used for the first time in the country from a simple colony showing its feactibility for the monitoring of toxigenic and non toxigenic P.multocida strains.