58 DISEASES OF THE LUNGS 



Catarrhal Pneumonia (Bronchopneumonia). — ^Definition. — 

 An inflammation of the lungs affecting isolated lobules or 

 groups of lobules, the exudate and desquamated cells in the 

 alveoli seldom undergoing fibrinous coagulation. 



Occurrence. — ^Most common in very young or aged animals. 

 Less frequent in the horse than in the ox, sheep, and swine. 



Etiology. — Catarrhal pneumonia occurs either as a primary 

 or as a secondary affection. As catarrhal pneumonia is 

 clinically a collective term it includes a group of pneu- 

 monias, the causes of which are varied. It may be due to: 

 (a) The spreading of bronchitis to the lung parenchyma; (6) 

 food entering the windpipe in patients suffering from 

 dysphagia (tetanus, milk fever, feeding too soon after 

 chloroform narcosis); (c) foreign matter (dust, sand, saw- 

 dust) which may be drawn into the lungs in recumbent 

 patients; (d) the aspiration of pus, blood, saliva or mucus 

 (head operations, patient recumbent) ; (e) unskilled admini- 

 stration of medicines, especially drenches;^ ■(/) result of 

 hypostasis of the lungs (recumbent position, long stable 

 confinement in old horses); (g) infection, especially with 

 the Bacillus bipolaris septicus (in the ox) and the Bacillus 

 pyogenes. 



Cold, bad sanitation and exhaustive railway and ship 

 transportations are predisposing factors. 



Catarrhal pneumonia is secondary to several acute infec- 

 tious diseases as malignant head catarrh, hog-cholera, 

 hemorrhagic septicemia; it often accompanies tuberculosis, 

 glanders, and occasionally actinomycosis. 



Symptoms. — ^The prodromal symptoms are those of 

 bronchitis which it usually follows. As the areas of solidi- 

 fication in the lung may be small and scattered, they are 

 difficult to detect clinically. The cardinal symptoms are: 

 Cough which is short, dull, and often painful, the patient 

 trying to suppress it. Nasal discharge which is at times 

 copious and white in color. Fever which may run about 

 104° F. The fever does not take a typical course as in 

 fibrinous pneumonia, but is intermittent in character, con- 

 tinuing until the termination of the disease. In aged 

 horses fever is often absent. Dyspnea, the respirations are 

 accelerated, and labored. Percussion is often painful and 



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