354 DISEASES OF BREATHINGr. 



of the nostrils and eyelids are red, congested, and frequently tinged 

 yellow with bile. There is often a slight, " rusty," yellow discharge 

 from the nostrils. The eyes are bloodshot. If the attack be but 

 sli2"ht, the exudation mav become absorbed before consolidation 

 sets in, and the lungs may recover their healthy condition without 

 further change. 



If the horse does not succumb during the first stage, the fever 

 gradually subsides ; the pulse falls ; the temperature becomes 

 lower; the appetite returns; and the ui'ine, which was previously 

 scanty, is abundant. The rate of breathing, which had decreased 

 with the abatement of the fever, now increases in rapidity, in 

 order to make up for the partial loss of function which the lungs 

 have sustained, owing to the consolidation of a portion of their 

 substance. In the third stage, the cough, if present, is moist and 

 full. There is a free discharge of phlegm, etc., from the lungs, 

 and, if the case ends favourably, the breathing becomes 

 normal. 



Pleurisy 



is inflammation of the pleurae, which become dry during the first 

 stage of the attack; hence the observer, on applying his ear to 

 the horse's side, may ascertain the presence of the disease by 

 hearing the crackling, or " friction sound " caused by the dry and 

 inflamed surfaces of the pleurae rubbing against each other, as 

 the lungs move backwards and forwards against the sides of the 

 chest when the animal breathes. The sound somewhat resembles 

 that emitted by two dry pieces of bladder when rubbed together. 

 Owing to the pleurae forming closed serous sacs, we always have, 

 after an attack of pleurisy, an effusion of serous fluid into them, 

 constituting " water on the chest " (hydrothorax) of A^arying 

 (]uantity. There is, also, an exudation, which is deposited on the 

 pleurae, and which becomes more or less organised. 



SYMPTOMS OF PLEURISY.— Pleurisy generally attacks only 

 one side of the chest, that being the right, in most cases. At 

 first, the symptoms usually resemble those of colic, except that 

 the pain is constant and not intermittent, and there is inflamma- 

 tory fever. The horse shows great disinclination to move. There 

 is considerable distress. In mild cases, the colicky pains are often 

 absent. A shivering fit frequently precedes the attack. The 

 affected side is tender to the touch. The breathing is quick and 

 sliort, and the flanlvs heave^ — which fact shows that the animal 

 endeavours to breathe as much as possible by the action of the 

 mufecles of the abdomen, and not by the movement of his ribs. 



