DISEASES OF HORSES 389 



to diseased or weakened blood vessels, the animal remains subject to 

 subsequent attacks. 



COMPRESSION OF THE BRAIN. 



Causes. In injuries from direct violence a piece of broken 

 bone may press upon the brain, and, according to its size, the brain 

 is robbed of its normal space within the cranium. It may also be 

 due to an extravasation of blood or to exudation in the subdural or 

 arachnoid spaces. Death from active cerebral congestion results 

 through compression. The occurrence may sometimes be traced to 

 the direct cause, which will give assurance for the correct diagnosis. 



Symptoms. Impairment of all the special senses and localized 

 paralysis. All the symptoms of lessened functional activity of the 

 brain are manifested to some degree. The paralysis remains to be 

 our guide for the location of the cause, for it will be found that the 

 paralysis occurs on the opposite side of the body from the location of 

 the injury, and the parts suffering paralysis will denote, to an expert 

 veterinarian or physician, the part of the brain which is suffering 

 compression. 



Treatment. Trephining, by a skillful operator, for the removal 

 of the cause when due to depressed bone or the presence of foreign 

 bodies. When the symptoms of compression follow other acute dis- 

 eases of the brain, apoplectic fits, etc., the treatment must be such as 

 the exigencies of the case demands. 



CONCUSSION OF THE BRAIN. 



Causes. This is generally caused by an animal falling over 

 backward and striking his poll, or perhaps falling forward on his 

 nose; by a blow on the head, etc. Train accidents during shipping 

 often cause concussion of the brain. 



Symptoms. Concussion of the brain is characterized by giddi- 

 ness, stupor, insensibility, or loss of muscular power, succeeding im- 

 mediately upon a blow or severe injury involving the cranium. The 

 animal may rally quickly or not for hours ; death may occur on the 

 spot or after a few days. When there is only slight concussion or 

 stunning, the animal soon recovers from the shock. When more 

 severe, insensibility may be complete and continue for a considerable 

 time ; the animal lies as if in a deep sleep ; the pupils are insensible 

 to light ; the pulse fluttering or feeole ; the surface of the body cold, 

 muscles relaxed, and the breathing scarcely perceptible. After a 

 variable interval partial recovery may take place, which is marked 

 by paralysis of some parts of the body, often a limb, the lips, ear, 

 etc. Convalescence is usually tedious, and frequently permanent 

 impairment of some organs remains. 



Pathology. Concussion produces laceration of the brain, or at 

 least a jarring of the nervous elements, which, if not sufficiently se- 

 vere to produce sudden death, may lead to softening or inflamma- 

 tion, with their respective symptoms of functional derangement. 



Treatment. The first object in treatment will be to establish 

 reaction or to arouse the feeble and weakening heart. This can often 

 be accomplished by dashing cold water on the head and body of the 

 animal ; frequent injections of weak ammonia water, ginger tea, or 



