Acute Pleurisy in the Horse. Pleuritis. 241 



pleurisies, other germs that have been lurking harmless in the 

 system may take occasion by reason of the lowered vitality in- 

 duced by a chill, or a trauma, to colonize the thoracic serosa and 

 develop pleurisy. Under such a theory, the predisposing and 

 microbian element would remain equally effectual, but only oper- 

 ative when conjoined, neither being pathogenic without the other. 



Until the constancy of the microbian factor is demonstrated we 

 must recognize the time honored doctrine, that pleurisy may be 

 due to cold, exposure, over exertions, to traumatic injuries, blows, 

 concussions, fractures, penetrating wounds, and to extension by 

 contiguity from adjacent diseases. 



Most commonly pleurisy is unilateral on the right side but is 

 often on the left or on both stdes. 



Symptoms. There is the early symptom of shivering followed 

 by a hot stage in which the limbs participate and partial sweats 

 bedew the surface. There are first uneasy movements of the fore 

 limbs with some lifting of the flanks and this discomfort increases 

 until the patient is panting with pain and occasionally glancing 

 round at his heaving flanks and even pawing as in colic. If the 

 pleurisy is confined to one side the corresponding fore limb is 

 often advanced before the other. The temperature is 102° and 

 upward. The pulse is quick, hard and incompressible being 

 usually compared to a jarred wire and beats from 48 to over 60 

 per minute. The breathing is highly characteristic. It is hurried, 

 is carried on chiefly by the abdominal muscles to avoid the rubbing 

 of the inflamed pleurae on each other, and has the inspiration 

 short and suddenly checked by an audible closure of the glottis 

 while the expiration is slow and prolonged. This character of 

 the breathing is well observed when the ear is placed against the 

 false nostril. The laboring abdominal muscles stand out as a 

 ridge from the outer angle of the ilium along the lower ends of 

 the last ribs (pleuritic ridge). A tremor on this line is often 

 noticeable in the early stages. It may also be felt by the hand 

 laid on the costal region. The horse does not stand obstinately 

 still as in pneumonia, but frequently moves as if seeking an easier 

 ■posture. The short, hacking cough contrasts with the deep, rare 

 cough of pneumonia. The expired air is not so hot, nor the 

 mucous membrane of the nose so red as in the last named disease 

 and there is no nasal discharge. A twitching of the muscles of 



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