500 PNEUMONIA. 



tion, which, as a rule, have no tendency to undergo ulterior 

 change. 



When making examination of lung-structure in animals 

 which have been sufferers from pneumonia, it is not common 

 that the diseased action is found attacking both lungs Avith 

 the same severity. Bilateral or double pneumonia is rare in 

 all animals ; still there is little doubt that in its common form 

 of broncho -pneumonia in the horse it is met with in both 

 lungs, the right being oftener and more extensively invaded 

 than the left. 



Sjrmptoins. 1. General. — As it rarely happens that in the 

 horse pneumonia is encountered as a pure and uncomplicated 

 disease, we may only speak of those cases where the indications 

 lead us to believe that the true lung-tissue is more largely 

 affected than the bronchial membrane or the pleural covering. 

 Seeing that the more numerous attacks of pneumonia are 

 accompanied, or rather preceded, by cataiTh, we can readily 

 understand that a very early, if not the earliest, symptom may 

 be cough, which most likely occurs, or has continued for some 

 days, without attracting much notice, until certain well-marked 

 febrile symptoms exhibit themselves. There may be occasional 

 rigors, with an open and staring coat ; there is disturbance of 

 animal heat, with coldness of skin and extremities, all con- 

 nected with perturbed nutrition. Accompanying these there 

 is languor, capricious appetite, injected, or dull, or rusty- 

 coloured visible mucous membranes ; the pulse is increased in 

 frequency, vessels feeling tolerably full, but the pulsations 

 obscure, sometimes small ; the temperature elevated from three 

 to four degrees, and respirations slightly accelerated. 



Although febrile symptoms such as these are generally 

 observed in the earlier stages of pneumonia, it not unfrequently 

 happens that considerable progress has been made in the 

 process, and distinct consolidation of lung-tissue exists ere the 

 symptoms of illness are sufficient to direct our attention to the 

 chest. As in many other chest affections, the horse is not 

 disposed to lie, occasionally moving listlessly around the box if 

 at liberty, and inclined to stand where fresh air is finding the 

 readiest entrance. 



It is deserving of notice that Avhen the febrile symptoms are 

 fully developed, and the pneumonic changes established, these 



