Stringhalt 295 



STEINGHALT, CHOREA 



Chorea is a disease known by a spasmodic contrac- 

 tion of some of the voluntary muscles. The muscles 

 twitch or tremble. The cause and real nature of this 

 disease are not known. It is similar to St. Vitus' dance 

 in the human family. It usually occurs in animals of 

 a nervous disposition. Chorea in some of its forms 

 is frequently seen in horses and dogs ; in the latter it 

 sometimes occurs as a sequel to distemper. It is prob- 

 able that several diseases, or symptoms of several dis- 

 eases, are confounded loosely under the general term 

 chorea by the layman ; but for practical purposes here 

 they may all be considered together. 



There are several forms of the disease, and the 

 symptoms vary accordingly. One of the most frequent 

 forms is stringhalt in horses. This is a marked spas- 

 modic jerking up of the hind leg as the horse travels. 

 In some cases it is seen only when the horse first starts, 

 after standing in the stall, and disappears after a few 

 steps have been taken. There is a form of stringhalt 

 that sometimes follows punctured wounds of the foot, 

 and disappears as soon as the wound heals. Another 

 form of chorea is shown by the inability of the horse 

 to lift the hind foot, which seems to be fastened to 

 the floor. When he does get it loose it is lifted up 

 high, and is held a moment in that position. This 

 form of the disease is called "immobility," and is most 

 pronounced on making the horse "stand over" quietly, 

 after he has stood in the stable for a time, especially 

 over night. The symptoms usually disappear if the 



