Pericardite em suínos ao abate no Rio Grande Sul: Avaliação de agentes bacterianos e lesões associadas

Abstract

The objective of the study was to identify the frequency of macroscopic and microscopic lesions and bacterial agents involved with pericarditis in slaughter pigs in the State of Rio Grande do Sul, Brazil. The samples were collected in slaughterhouses with Federal Inspection Service (SIF) between February and October, 2010. Condemnation due to pericarditis in the examined animals was 3.9% (299/7,571). Ninety one cases of pericarditis were examined and by histopathology 89% were chronic and 47% of the corresponding lungs showed chronic pleuritis, but there was no significant association between both lesions. The bacterial agents isolated from the hearts were Streptococcus spp., Pasteurella multocida, Haemophilus parasuis and Streptococcus suis. Bacterial DNA from Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae were the most frequently detected by PCR. There was significant association between isolation of P. multocida and Streptococcus spp. in the hearts and corresponding lungs. The results suggest that lung infection could act as a port of entry to the colonization of the adjacent pericardium. In spite of the fact that M. hyopneumoniae was the agent more frequently identified by PCR in the heart and corresponding lung, there was no significant association of the agent in the organs. This suggests that the infections were independent events. The other agents investigated did not show significant association between isolation or DNA detection in heart and corresponding lungs. Another important finding was the presence of coinfection between bacterial agents in 2% of the hearts and by PCR were identified bacterial DNA of two or more agents in 16.5% of the hearts. These results suggest that coinfections in cases of pericarditis need further investigation.