Statistical Evidence for a Link between Bronchopneumonia and Disseminated Focal Nephritis in Pigs

Abstract

Summary An investigation on the occurrence of different pneumonia types and their possible concurrence with other pluck organ disorders was made on 6,565 pigs presented at slaughter. The frequency of disseminated focal nephritis in a bronchopneumonia group and a non‐bronchopneumonia residual group, respectively, was found to differ significantly from the mean frequency of nephritis in all pig plucks examined. The number of lesioned kidneys in each of 28 samples contributing to the bronchopneumonia group and in each of 8 samples contributing to the residual group was regressed group‐wise on the number of individual plucks examined in each sample; the correlation coefficient for each of these two groups was calculated. These calculations showed a highly significant link between bronchopneumonia and disseminated focal nephritis. The histopathological and bacteriological examination of some lung and kidney lesions representing the bronchopneumonia group substantiated this finding. It is concluded that the two diseases are connected through dissemination, and that Pasteurella multocida is the organism involved in the majority of cases.

Occurrence and associated lesions of Pasteurella multocida in porcine bronchopneumonia

“…Pericarditis has previously been found in association with porcine bronchopneumonia (Buttenschon 1991;Christensen & Enoe 1999), but a high frequency of cultivation of P. multocida from the pericardial sac has not been reported (Buttenschon et al 1997). In this study pericarditis was found in 18 out of the 114 cases of bronchopneumonia with positive cultivation of P. multocida.…”

“…The findings of pericarditis and positive cultivation of P. multocida from the pericardial sac indicate that bronchopneumonia associated with P. multocida is a part of a more complex disease pattern affecting other organ systems in addition to the respiratory tract. In the study by Buttenschon (1991), a connection between bronchopneumonia and cases of focal or diffuse nephritis at the gross level was observed.…”

“…P. multocida is generally recognized as a secondary invader contributing substantially to respiratory diseases in pigs by aggravation of lung lesions (Falk et al 1991;Pijoan 2006;Hansen et al 2010). Systemic spreading of P. multocida capsular serotype A from lung lesions has been reported in natural infections by Buttenschon (1991) and Pijoan and Fuentes (1987). Likewise in experimental infection a systemic spread of the bacterium has been reported (Ono et al 2003).…”

“…Furthermore, a high incidence of isolation of P. multocida was found in both bronchopneumonia (29 of 49 cases) and nephritis (19 of 49 cases) (Buttenschon & Rosendal 1990;Buttenschon 1991).…”

“…Lesions associated with P. multocida are usually characterized by exudation into bronchi and bronchioles, but necrosis of lung tissue and sepsis may also be observed (Roberts et al 1962;Pijoan & Fuentes 1987;Mackie et al 1992;Cameron et al 1996;Pijoan 2006). In addition, characterization and comparison of isolates of P. multocida from porcine lungs and internal organs thus indicate a systemic spreading of the bacterium may take place (Buttenschon & Rosendal 1990;Buttenschon 1991;Lainson et al 2002). Indications of systemic spreading of P. multocida have so far mainly been based on cultivation.…”