Diseases of the Chest. \TI 



jerk. It is significant of the early stage of pleurisy, and arises 

 from the desire to avoid the pain attendant on the rubbing together 

 of the inflamed surfaces during deep inspirations. It is further 

 seen in tetanus, peritonitis, pericarditis and pleurodynia. 



Deep breathing with great lifting of the flanks and loins is 

 characteristic of water in the chest, and consequent inability to 

 inflate the lungs. 



Labored breathing, which is at once hurried, deep, and with- 

 out intermission, is seen in severe laryngitis, croup, capillary 

 bronchitis, and pneumonia, in all cases alike from the difficulty 

 experienced in introducing into the lungs the requsite amount of 

 air. It is especially marked in double pneumonia, pleuro-pneu- 

 monia, complicated with effusion in the chest, and in old standing 

 broken wind with dilatation of the right heart. 



In all such cases where there is much interference with the 

 aeration of blood, whether from obstruction to the circulation of 

 blood or a hindrance to the introduction of air, the horse invaria- 

 bly stands. The fact that he has lain down may be taken as an 

 indication that improvement has taken place. The peculiarity is 

 due to the sharp outline of the horse's sternum inferiorly so that 

 in lying down he is compelled to rest on his side and the whole 

 weight of the body tends to compress the chest. In the ox, 

 sheep, pig and dog, which can rest on the sternum, breathing 

 can be carried on with comparative ease in the recumbent posi- 

 tion, and these animals accordingly do not necessarily stand 

 except in very extensive and violent affections of the chest. 



The occurrence of a short inspiration suddenly checked and a 

 prolonged expiration characterizes pleurisy, the check to the in- 

 spiratory act being because of the pain caused by dilating the 

 thorax. 



The double lifting of the flank in expiration : — the act appear- 

 ing to be performed by two distinct and successive acts is one of 

 the most prominent symptoms of broken wind, but is not peculiar 

 to this disorder. In the horse it exists in chronic bronchitis, dil- 

 atation of the right heart, old standing hydrothorax, and 

 diaphragmatic hernia. It is further frequent in the acute diseases 

 of the chest. In oxen it accompanies pulmonary emphysema, 



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