Pasteurella multocida type A as the primary agent of pneumonia and septicaemia in pigs

Pasteurella multocida tipo A como agente primário de pneumonia e septicemia em suínos

Abstract:

In order to understand better the pathological aspects and spread of Pasteurella multocida type A as the primary cause of pneumonia in pigs, was made an experiment with intranasal inoculation of different concentrations of inocula [Group (G1): 10⁸ Colony Forming Units (CFU)/ml; G2: 10⁷ CFU/ml; G3: 10⁶ CFU/ml and G4: 10⁵ CFU/ml], using two pigs per group. The pigs were obtained from a high health status herd. Pigs were monitored clinically for 4 days and subsequently necropsied. All pigs had clinical signs and lesions associated with respiratory disease. Dyspnoea and hyperthermia were the main clinical signs observed. Suppurative cranioventral bronchopneumonia, in some cases associated with necrosuppurative pleuropneumonia, fibrinous pericarditis and pleuritic, were the most frequent types of lesion found. The disease evolved with septicaemia, characterized by septic infarctions in the liver and spleen, with the detection of P. multocida type A. In this study, P. multocida type A strain #11246 was the primary agent of fibrinous pleuritis and suppurative cranioventral bronchopneumonia, pericarditis and septicaemia in the pigs. All concentrations of inoculum used (10⁵-10⁸ CFU/ml) were able to produce clinical and pathological changes of pneumonia, pleuritis, pericarditis and septicemia in challenged animals.

Index Terms:
Swine pasteurellosis; necrosuppurative pleuropneumonia; sepsis.