92 SWINE DISEASES 



with forage poisoning associated with pharyngeal paraly- 

 sis. Sometimes it is a sequel to croupous pneumonia. 



Etiology. The usual cause of septic pneumonia is 

 the introduction of foreign substances into the lung. In 

 cases of pharyngeal paralysis food escapes into the air 

 tube. Drenching is another means by which foreign 

 substances are frequently introduced into the lung. 

 Thrombic obstruction of vessels supplying an area 

 affected with croupous pneumonia favors the action of 

 saprophytic bacteria, and hence putrefaction and the 

 production of septic pneumonia. Abscesses sometimes 

 become infected with putrefying organisms and produce 

 septic pneumonia. The Bacillus necrophorous is active 

 in the production of necrosis and putrefaction in the lung. 



Lesions. Necrotic centers are most frequently found 

 in the dependent and anterior part of the lung. The 

 foci vary in size from that of a pea to a baseball, and 

 may be few or many. They appear dirty brown, red, 

 or dirty white in color. When incised they are found to 

 be soft, the content being semifluid in the early stages 

 but later of a cheesy consistency. The surrounding 

 lung tissue will be inflamed. In the beginning, an 

 infiltration circumscribes the lesions, but in the older 

 lesions there may be a distinct capsule. Superficial 

 necrotic foci may be associated with pleurisy. 



Symptoms. The first symptom evidencing septic 

 pneumonia is the foul-smelling exhaled air. This symptom 

 does not occur in all cases, as the escape of putrid odors is 

 dependent upon the erosion and discharge into the bron- 

 chial tubes of necrotic putrid material. Rise of tempera- 

 ture accompanies practically all cases of septic pneumonia. 

 The fever may be irregular and intermittent, the thermal 

 disturbance depending upon absorption of septic products. 

 In those cases of croupous pneumonia in which septic 

 pneumonia is a sequel, the general symptoms will be the 

 same, plus the offensive breath, as those observed in a 

 case of croupous pneumonia A microscopic examination 

 of the nasal discharge will reveal the presence of shreds 

 of disintegrated lung tissue in cases of septic pneumonia, 



