202 CHAPTER 22. 



408. Nature of the diseases affecting the organs of Respiration. 



Most of the diseases of the organs of Respiration are of an inflamma- 

 tory character. Such, for instance, are Catarrh, Laryngitis, Sore throat, 

 Bronchitis, Pleuritis, Pneumonia, and Pleuro-pneumonia. Other dis- 

 eases, though not in themselves inflammatory, yet generally result from 

 attacks of inflammation. Such are Broken wind, Thick wind, Chronic 

 cough, Nasal gleet, Roaring, &c. 



409. Causes of disease of the organs of Respiration. 



Diseases of the organs of Respiration nearly always have their origin 

 in preventible causes, which may be briefly summed up under the great 

 heads of insufficient ventilation, want of cleanliness in the stable, and 

 bad stable management. Under this latter head we include not only 

 neglect of servants, but also faults of the owner or rider, such as allow- 

 ing a horse when sweating to stand till chilled, or riding too far or too 

 fast, or working a horse on a full stomach, or when out of condition. 



Great and sudden changes of temperature, such as from grass to 

 stables, especially if accompanied by injudiciously sudden alteration of 

 diet from grass to corn, which is calculated to produce plethora in the 

 system and thereby increased liability to inflammatory attacks, are also 

 ready and frequent causes. Hence young horses, when first stabled, are 

 apt to suffer. 



Some cases of disease no doubt arise from sudden atmospheric changes, 

 but these with good stable management will be rare. Horses standing in 

 town stables are more liable, as we might expect, to suffer from diseases 

 of the respiratory organs than those in country districts. 



Diseases of the lungs and air-passages constitute more than half the 

 ailments to which horses are subject. They prevail most during ex- 

 tremes of temperature, whether of heat or of cold, and are frequent in 

 the spring and autumn when the change of coat is taking place. 



COUGHS. 



410. Cause of Cough. 



Cough is a symptom of disease rather than a disease in itself. It 

 arises from irritation existing in some portion of the respiratory struc- 

 tures. 



The nature of a cough is a valuable guide as to the part in which the 

 irritation exists, and also as to the degree and stage of the disease from 

 which the irritation arises. By applying the ear to the various parts of 

 the larynx, trachea, front of the chest, or to the sides whilst the animal 

 is coughing, much valuable information may sometimes be gained as to 

 its seat and nature. 



