DISEASES OF THE RESPIRATORY ORGANS. 109 



111 chronic roaring there is no evidence of any disease of the huynx 

 other than the wasted condition of the muscles in (luestion. The 

 disease of tlie nerve is generally far from the larynx. Disease of 

 parts contiguous to the nerve along any i)art of its course may inter- 

 fere with its proper function. Enlargement of lymphatic glands 

 within the chest through which the nerve passes on its way back 

 to the larynx is the most fre(iueiit i.uterruption of ncivous supply, 

 and consetpiently roaring. "When loariug hecomes conlirmcd, medical 

 treatment is entirely useless, as it is impossible to le.store the wasted 

 muscle and at tin* same time remove the cau>c of the intcnuplioii 

 of the nervous supply. Before roaring becomes i)ermanent the con- 

 dition may be benefited by a course of iodid of potassium, if caused 

 by disease of the lymphatic glands. Electricity has been used with 

 indifferent success. Blistering or firing over the larynx is. of course, 

 not worthy of trial if the disease is due to interference of the nerve 

 supply. The administration of strychnia (nux vomica) on the 

 ground that it is a nerve tonic with the view of stimulating the af- 

 fected nniscles is treating only the loult of the disease without con- 

 sidering the cause, and is therefoie useless. The operation of extir- 

 l)ating the collapsed (^artilage and vocal cortl is believed to be the 

 oidy relief, and, as this operation is critical and can be performed 

 only by the skillful veterinarian, it will not be described here. 



From the foregoing de^criittion of the disease it will be seen that 

 the name " roaring," by which the disease is generally known, is only 

 .1 symptom and not the disease. Chronic roaring is also in many 

 cases accompanied with a cough. The best way to test whether a 

 liorse is a "roarer" is either to make him pull a load rapidly up a 

 hill or over a sandy road or soft giound; or, if he is a saddle horse, 

 gallop him up a hill or over soft ground. The object is to make him 

 exert himself. Some horses require a great deal more exertion than 

 t)thers before the characteristic sound is emitted. The greater the 

 distance he is forced, the more he will appear exhausted if he is a 

 roarer; in bad cases the animal becomes utterly exhausted, the 

 breathing is rapid and difticult, the no.strils dilate to the fullest ex- 

 tent, and the animal appears as if suffocation was imminent. 



An animal that is a roarer should not be used for breeding i)ur- 

 poses. The taint is transmissible in many instances. 



(rrunflnf/. — A conunon test used by veterinarians when examining 

 '• the wind " of a horse is to see if he is a '' grunter." This is a sound 

 omitt€»d during expiration when the animal is suddenly moved, or 

 startled, or struck at. If he grunts he is further tested for roaring, 

 (irunters are not always roarers, l)ut, as it is a common thing for a 

 roarer to grmit, such an animal must be looked upon with suspicion 

 until he is thoroughly tried by pulling a load or galloped up a hill. 

 The test should be a severe one. Horses sutfcring with pleurisy, 



