Dyspnoea Laryngea. Roaring. Hemiplegia Laryngea. 141 



breathing nor any change of appetite attested the slightest devia- 

 tion from health. Reynal, Cruzel, Caffin, Motte and Ayrault 

 mention similar occurrences. 



The paralysis of chronic lead poisoning will also cause roaring. 



Occasional or intermittent roaring. Puzzling cases are met 

 with in which a horse will roar at one time and not at another. 

 In such cases the veterinary profession has incurred an amount of 

 odium which was by no means deserved. Two veterinarians, 

 equally respectable and talented, appearing in a Court of Justice 

 to swear to the same animal which they had examined on different 

 days, respectively pronounce it a roarer or a sound horse, as it 

 happened to be at the time of the respective examinations. Such 

 cases have been differently accounted for. 



Slight colds or sore throats may cause roaring so long as they 

 persist. Tight reining with the nose drawn in toward the chest 

 induces a stridor in certain animals by distorting the larynx and 

 trachea. Some horses with thick necks, badly set on heads, and 

 in a state of obesity, roar, yet the symptom subsides when the 

 superfluous fat is got rid of and they are brought into hard work- 

 ing condition. Stallions are very liable to make a noise from this 

 cause. In a case of roaring which disappeared when the horse 

 had been exercised for some time Leblanc diagnosed an oedema of 

 the glottis which was absorbed under the increased movement of 

 the parts. He did not test his opinion by dissection. 



Roaring sometimes hereditary. That roaring runs in fam- 

 ilies there can be no doubt, but the direct cause appears to be 

 mostly the transmission of a faulty conformation. A head with 

 faulty shape and badly set on ; a thick, short neck, deficient in 

 mobility, or a small, narrow chest, predisposed to acute diseases, 

 descends from parents to offspring, entailing a predisposition to 

 roaring. The large Normandy horse is notoriously subject to 

 roaring, but then he is equally characterized by a big, coarse 

 head, narrow forehead and nostrils, big jowl, and narrow inter- 

 maxillary space. In all breeds this form is very subject to roar- 

 ing, because of the stiffness of the neck and tendency to com- 

 pression of the larynx. With the head badly set on, as it is 

 almost of necessity in these animals, everything is done to 

 produce roaring. Not only is the head cruelly reined in at work, 

 but the horse is kept a great part of his time in the stable in the 



