CHRONIC DISEASES OP THE ORGANS OF RESPIRATION. 225 



469. Class of horses predisposed to Broken Wind. 470. PULMONARY 

 CONSUMPTION. 



CHRONIC COUGH. 



450. Nature and seat of Chronic Cough. 



Chronic cough is a very troublesome affection. It may have its seat 

 either in or about the larynx, in the respiratory passages, or in the lungs. 



It usually arises from morbid sensibility of the nerves of the larynx, 

 or from irritability left in its lining membrane or in the bronchial tubes 

 after pneumonia, bronchitis or influenza. Or it may be connected with 

 indigestion, and indeed it may be said to be a symptom of that affection. 

 An intimate connection, as the reader is aware, exists between the nervous 

 system of the stomach and that of the lungs. Hence any derangement 

 of the former is apt to set up irritation in the latter. Thus horses 

 suffering from worms are often affected with Chronic cough. It also 

 constantly accompanies Broken Wind ; and in some cases it exists without 

 any appreciable cause. In horses subject to this disease very trifling 

 causes, such as the change from the atmosphere of the stable to the open 

 air, or the mere act of eating or of drinking, or a change of weather, or 

 a little unwonted excitement, such as a trot, or a sudden blow, are often 

 sufficient to produce irritation and consequently cough. 



Chronic cough, when following bronchitis or influenza, is usually 

 accompanied by an extra secretion of mucus ; but we sometimes find it 

 when the membrane is particularly dry. 



451. Treatment. 



The treatment of the malady must depend on the cause from which it 

 proceeds. 



When the Cough proceeds from irritability of the larynx, considerable 

 benefit even in cases of some standing will be found to result from the 

 application of external irritation to the throat. Blisters are usually 

 employed for this purpose, but the Author has seen much better results 

 from setons. The action of a seton can be maintained for any length 

 of time, which is an object of great importance in dealing with a chronic 

 affection ; and furthermore the horse may be worked as usual, whilst the 

 seton remains in. If setons are objected to on account of the blemish 

 likely to remain, repeated applications of the biniodide of mercury oint- 

 ment may be beneficially applied. With a view of allaying the irritation 

 which generally accompanies the passage of food down the throat, it is 

 useful to mix boiled linseed with the corn ; and five or six pounds of 

 carrots may be given with the other food daily; or to horses in slow 

 work steamed food may be given. The tendency to irritation is dimi- 

 nished by giving food and water often, and in small quantities at a 

 time. 



If the cough proceeds from the lungs, or as a sympathetic affection, 

 the real cause, which is usually indigestion, must be treated. Careful 



15 



