INFLAMMATION OF THE LUNGS. 305 



dition, travel great distances to markets or fairs. A cause 

 is observed to particularly operate in some seasons : cold 

 moist spring seasons are often marked with pneumonic 

 attacks, which rage in an epidemic form. 



Symptoms. — This disease sometimes attacks the horse 

 very suddenly, and he exhibits, with one or two shivering 

 fits, the excited breathing which is symptomatic of the 

 complaint ; at others, it steals on, and is almost unobserved 

 for two or three days ; but whether the approach be sudden 

 or retarded, the general functions will appear disturbed. 

 One that first shows itself is the unequal distribution of 

 heat ; the legs and ears being much colder than the other 

 parts of the body. The coat stares ; the horse loses his 

 appetite ; is evidently uneasy, and occasionally looks gently 

 round towards his chest. In the early stages the nasal 

 linings look paler than usual ; but as it advances they be- 

 come of a leaden hue ; and although the general surface of 

 the trunk may vary in its temperature, the extremities, 

 as the legs, ears, and tail, and sometimes the muzzle, 

 are found uniformly cold. Cough is by no means a 

 pathognomonic symptom ; many cases are without it ; 

 but when it does exist, it is at first short, dry, and 

 frequent, and becomes eventually heavy, thick, and painful ; 

 occasionally some mucus with bloody striae is thrown up in 

 coughing, particularly when the bronchii participate in the 

 affection. The respiration becomes disturbed as soon as 

 the disease is formed ; the first febrile attack will hurry it, 

 but, the exacerbation of that over, it becomes simply 

 laboured. The local inflammation having pervaded the sub- 

 stance of the lungs, thickened the lining membrane of the 

 tubes, and lessened the calibre of the air cells, respiration 

 now becomes permanently quickened ; the flanks are found 

 to heave, and the breathing is carried on with labour and 

 irregularity ; the inspirations being delayed to retard the 

 pain produced by the distention of the chest, while the 

 expirations are more hurried to relieve it from distress. 

 The cavity is, however, no sooner emptied, than a new 

 source of distress, in the stagnant condition of the heart, 

 forces the horse to renew the breathing. The state of the 

 pulse is variable in this disease, according as the lungs or 

 the pleura bear the greatest share in the complaint. It is, 



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