DISEASES OF THE NERVOUS SYSTEM. 14! 



are unacquainted, The symptoms are drowsiness, hanging 

 of the head, dulness, snoring respiration. The pulse is 

 slower than normal. On being made to walk out, the animal 

 shows a tendency to stagger, trip, and sometimes fall. 



Treahnent. — Not very much can be done to relieve the 

 condition, except perhaps to administer an occasional pur- 

 gative. Work lightly, and pay proper attention to feeding, 

 etc., endeavouring to preserve the general health. It is 

 a prpgressive disease, and sooner or later causes death. 



CHOREA. 



Definition. — A disease of the nervous system, charac- 

 terized by involuntary and convulsive muscular move- 

 ments. It is a somewhat frequent disease in dogs and 

 horses. It occurs in several forms, the most common 

 of which, in the horse, is known as ' stringhalt,' affecting 

 the flexor and extensor muscles of the hind-legs. In the 

 dog, usually the muscles of the head and neck are affected, 

 or perhaps the voluntary muscles of the whole body. In the 

 horse, the muscles of a hind-leg, or a fore-leg, and sometimes 

 the muscles of the whole body, are affected. In such a case it 

 is known as 'shivers.' In the human being the same con- 

 dition has received the name of St. Vitus' dance. 



Stringhalt. — May be defined as a violent spasmodic jerk- 

 ing, or irregular movement of one or both hind-legs, due to 

 irregularly distributed nervous influence. 



It is caused by some lesion or abnormal condition of the 

 nervous system. Some contend that it is a disease of the 

 spinal cord, and others say that the trouble is due to some 

 affection of the brain. Again, it is said to be due to 

 irregular distribution of nervous influence to the extensors 

 and flexors of the limb. This latter is probably the correct 

 opinion ; but, at the same time, it is not explained why the 

 nervous influence is so irresjularlv distributed. But it can 



