346 LUNGS AND PLEURA. 



rare, and others resulting in chronic pneumonia have not been 

 authoritatively described. 



Pneumonia is distinguished from broncho-pneumonia by the exist- 

 ence of dulness at the period of crisis, whilst in the case of broncho- 

 pneumonia this period is only marked by partial dulness, which is even 

 then sometimes slight. Moreover, broncho-pneumonia usually develops 

 much more slowly. 



The disease, then, is distinguished from peripneumonia by the 

 following points : — 



(a) By the character of the temperature curve, which is regular in 

 pneumonia, only attaining its highest point at the period of crisis, whilst 

 in peripneumonia it ascends suddenly, and presents sudden oscillations. 



(b) The appetite remains, although diminished. 



(c) Sensitiveness in the region of the ribs is but feebly marked, or is 

 entirely absent, simple pneumonia not being accompanied by pleurisy. 



(d) The dewlap never shows oedema, a symptom which usually 

 accompanies the period of crisis in peripneumonia, when the jugular 

 veins and the anterior vena cava are compressed. 



{(') These signs alone are almost sufficient on which to base the 

 diagnosis, but they are often supplemented by two others, of some 

 what less importance (for in exceptional cases they may also be 

 observed in simple pneumonia), viz. — the absence in most instances 

 of a membranous sound, and of a well-marked souffle. 



Prognosis. Two-thirds of the cases recover. This proportion might 

 be increased if the veterinary surgeon were called in at the beginning. 



Lesions. Post-mottem examination reveals neither pleural exudate 

 nor pleural lesions. The lung is large and of increased weight, hepatised 

 along its lower borders, and congested in its upper part. 



The sero-haemorrhagic infiltration of the interlobular spaces varies, 

 according to the region examined : the upper regions are engorged and 

 black, owing to capillary haemorrhages and blood clots, which completely 

 surround the pulmonary lobule, the latter being violet or brownish-red 

 in colour. In the hepatised portions the lobules are of a washed-out 

 reddish tint, and the interspaces of a whitish colour. 



The bronchi are filled with frothy, whitish mucus; the small bronchi 

 sometimes contain fibrous concretions and the mucous membrane is 

 injected, and may be destroyed in places. The bronchial lymphatic 

 glands are enlarged, congested, and contain small haemorrhages. 



It is important in making a post-mortem examination to be able to 

 distinguish pneumonia from . peripneumonia. This is comparatively 

 easy if one bears in mind that in the latter pleurisy always exists, 

 that the interlobular connective tissue spaces are always greatly dis- 

 tended with a citrine-coloured serosity, that on section the peripneu- 



