88 SWINE DISEASES 



Catarrhal Pneumonia 



Catarrhal pneumonia is a lobular involvement char- 

 acterized by occlusion of the air cells, with exudate and 

 desquamated epithelium. 



Etiology. Catarrhal pneumonia is practically always 

 a sequel of bronchitis and is therefore produced by the 

 same causative factors. Bacillus pyocyaneus may cause 

 catarrhal pneumonia. Catarrhal pneumonia is one of 

 the characteristic lesions of swine plague due to the 

 Bacterium suisepticus. (Description will be found in 

 Chapter VIII.) Bronchopneumonia is occasionally sec- 

 ondary to other diseases, such as hog cholera or septi- 

 cemia. 



Lesions. The inflammatory process is confined to 

 a lobule or a group of lobules. As the disease progresses, 

 other adjacent lobules may become involved, the affected 

 areas thus becoming confluent and larger. In the 

 beginning the affected areas are hyperemic. The alveoli 

 soon become filled with inflammatory exudate which is 

 at first fluid but later coagulates and becomes dry, the 

 diseased lobules thus becoming solid. These areas are 

 first red in color, but early become brown, gray, then 

 yellow or yellowish-white, and if the condition persists 

 abscess formation may occur. Bronchitis is usually 

 associated with bronchopneumonia and in such cases the 

 lesions characterizing bronchitis would also be present. 



Symptoms. Catarrhal pneumonia in swine is ex- 

 tremely difficult to differentiate from bronchitis because 

 of the inability to efficiently auscultate or percuss the 

 thorax. Catarrhal pneumonia offers the same general 

 symptoms that have been noted in bronchitis, except 

 that pneumonic symptoms are usually more intensive 

 than those of bronchitis. Catarrhal pneumonia has no 

 definite course, the length or duration of the disease 

 depending upon the cause, extent of the disease, and the 

 resistance of the affected animal. The disease is most 

 fatal in young swine. 



Treatment. Medicinal treatment other than in- 

 halation of medicated vapors is of little or no value. 



