34 RURAL VETERINARY SECRETS 



SYMPTOMS 



Usually in primary cases the disease comes on gradually. It 

 is at first but slightly developed, the patient only emitting a noisy 

 sound when exercising. As a rule, if the horse be at rest, no signs 

 of the disorder are noticed. If the upper rings of the trachea be 

 pinched, a prolonged, hoarse throat cough is heard. In many 

 instances, however, cough is absent. It is sometimes possible to 

 cause the patient to emit a peculiar grunt if it is struck a sudden, 

 unexpected blow with the hand on the side of the chest. The prin- 

 cipal symptom of roaring, however, is the audible laryngial sound 

 emitted during and increased by exercise. The quality of the sound 

 suiTers many modifications from a whistle to a pronounced roar, 

 which in some animals can be heard a distance of several yards. 

 Pressing the throat with the index finger increases the sound. In 

 well developed cases sufficient exercise can produce interrupted 

 breathing. By compressing the nostrils to one-half their normal 

 dilation the sound is temporarily diminished. Generally the roaring 

 sound ceases after five to ten minutes rest, but returns again dur- 

 ing exercise. In mild cases it stops as soon as the animal is "pulled 

 up" after a hard gallop. 



DIAGNOSIS 



'i'lic examination of the patient should be made under motion. 

 The liorse may be ridden, galloped on a long line, or led behind 

 a buggy. In some mild cases tlic animal may suppress the sound 

 by extending the head. To axoid this the head should be dra\vn 

 in, the neck held well arched. The use of tlie laryngoscope is of 

 great value in diagnosis. 



The course of primary roaring is chronic. Due to the wasting 

 away of the muscles of the vocal cords on the left side, the condition 

 grows worse with time. ATany roaring horses may' be used for light, 

 slow work, while others are practically worthless for service. 



Some cases of secondary roaring (forage poisoning, laryngitis, 

 strangles) recover spontaneously in four to six months. About 80 

 ])cr cent can either be relieved or cured by surgical interference. 



TREATMENT 



Thenifjsl successful treatment consists in the removal of the 

 laryngeal saccule of the affected side. 



