566 NERVOUS DISEASES. 



on the Continent. It is stated that it rages like a true enzootic in 

 certain parts of the Alps, and of the Valley of the Rhone ; attacking 

 in preference brood mares and young horses of from six months to 

 three years of age* but seldom mules. There are certain stricken 

 farms on which horse-breeding cannot be carried on, as all the 

 young horses become attacked with immobilite by the time they 

 are one or two years old. In districts where this disease is 

 common, human beings are equally subject to brain affections. 



The SYMPTOMS are those of pressure on the brain, which con- 

 sequently suffers from partial absorption. There is more or less 

 loss of consciousness, feeling, and power of volition. The pulse 

 and respiration are slow, and there is an entire absence of fever. 

 The animal often shows a tendency to go round in a circle, and 

 during movement to raise his feet very high, as if he were passing 

 through a stream of water or crossing an obstacle (Friedberger and 

 Frohner). He pays little or no heed to sights, sounds, or blows. 

 He eats his food in an irregular manner, fast, slow, or at intervals, 

 and frequently holds a portion of grass or hay in his mouth for 

 a considerable time without moving his jaws. If the animal's legs 

 be placed in a constrained position, he will maintain it, although 

 it would be extremely irksome to him were he in health. A very 

 characteristic sign is dragging the fore legs on the ground when 

 the horse is made to rein back. This is not done by animals which 

 make a difficulty in reining back on account of want of training, 

 or pain in the loins. The expression and actions are those of 

 stupidity and insensibility to external impressions. Sometimes 

 the disease assumes an acutely inflammatory course, accompanied 

 by symptoms of excitement and delirium. 



TREATMENT, which may consist of strong purgatives (aloes or 

 Epsom salts) and iodide of potassium, is rarely of any use. 



Paralysis of the Face. 



The nerves (the seventh pair) which, on each side of the head, 

 supply the muscles of the lips, nostrils, cheeks, eyelids, and ears 

 with power of movement, on leaving the brain, issue respectively 

 through the canal of the internal ear, and gain the outside of 

 the cheek just below the joint of the jaw (Fig. 115, p. 297). They 

 pass, one on each side, along the cheek, close under the skin, to 

 the lips ; giving off, during this course, branches to their various 

 muscles. 



SYMPTOMS. — ^Drooping of the eyelid, inability to fully close the 

 eye, powerlessness to erect the ear, and difficulty of breathing. 



