DISEASES OF THE NERVOUS SYSTEM. 121 



of all surroundings, with complete loss of sensation and power; how- 

 ever, there may be some slight convulsive movements, but they are 

 without any effort of the will. 



Death may quickly follow the injury; or, if the injury has not been 

 very serious, recovery may take place in a comparatively short time; or 

 the animal may linger in a more or less unconscious state for a consid- 

 erable time, or there may be a partial recovery from the injury, followed 

 within a few days by encephalitis. 



The injury which produces concussion of the brain may at the same 

 time fracture one or more of the bones of the cranium. The fracture 

 may be simple a crack in the bone without depression, or the broken 

 bone may be depressed, the pressure on the brain substa-uce constitut- 

 ing compression of the brain. The first step in the treatment of com- 

 pression of the brain from the latter cause is to elevate the depressed 

 bone, which in some cases may be done with a thin but strong piece of 

 steel, like a knife blade. In many cases it is necessary to remove a 

 portion of bone with a trephine in order to be able to raise the depressed 

 part. Such cases require the skill of an expert veterinarian, but un- 

 less the animal is a yery valuable one it should be butchered as soon as 

 possible after the accident, and not allowed to linger until the meat 

 becomes unfit for consumption. 



Compression of the brain may result from an injury without fracture 

 of a bone. A blow on the head may rupture a blood-vessel within the 

 cranial cavity, and the blood escaping therefrom (either on the surface 

 of the brain or into the structure of the brain) produces compression 

 of the brain substance. Or the injury may cause inflammation, the 

 result of which may be compression due to the formation of pus. 



Compression from the escape of blood may be suspected when the in- 

 sensibility continues. But when due to the formation of pus the animal 

 partially recovers, and after three or four days have elapsed becomes 

 again unconscious. 



In concussion of the brain, during the first stage, when the surface 

 of the body is cold, cover the body and legs with warm blankets. It is 

 useless to attempt to administer medicines while the animal is insensible 

 and can not swallow. Cold water or crushed ice should bo applied to 

 the head, and when consciousness returns the purgative drench as mi- 

 vised for encephalitis should be administered. The animal should be 

 assisted to its feet and put in a comfortable place, free from light and 

 noise. Only small quantities of food, in the form of bran slops or grass, 

 should be given for some time. Bleeding should not be performed 

 unless the case runs into encephalitis, when the general treatment ad- 

 vised under that head may be followed. 



EPILEPSY. 



This affection is charav.teri/ed by the onset of sudden convulsions. 

 The animal may appear to be in a fair state of health, ;\s u general 



