DISEASES OF THE NERVOUS SYSTEM. 217 



It may follow bleeding or the rapid delivery of a foetus, or the 

 evacuation of a large quantity of exudate, as from the pleural 

 cavity, or diseases of or pressure on the blood-vessels. 



Ill-fitting harness, as a tight collar or throat-latch, producing 

 pressure on the jugular vein, may be a cause; then there is an 

 hereditary tendency in some cases, horses that are high headed 

 (star-gazers), long, narrow necks seem predisposed. 



Parasites in the blood-vessels may be a cause. 



What are the symptoms ? 



It usually occurs while the animal is hitched up; the horse 

 stops suddenly, shakes the head as though there was a fly in the 

 ear, trembles, and may fall down, or the attack passes off in a few 

 minutes. In some cases there is a tendency to run (termed running 

 staggers); this is when they are liable to do damage to themselves 

 and to property. 



A second or third paroxysm may come on if driven immediately 

 after the first attack. 



How is the diagnosis made ? 



By the symptoms coming on suddenly, by the condition of the 

 harness, etc. 



What is the prognosis ? 



It is good if no malformation or organic trouble exists. They 

 are all liable to re-attacks. 



What is the treatment for vertigo ? 



DuRiXG THE r'AEOXTSM, keep the animal as quiet as possible 

 to prevent injury to body and to property. Cold applications to 

 the head are useful; bromide of sodium or potassium may be given. 



Adjust the harness. These paroxysms tend to pass away and 

 the animal recovers without any treatment. The common practice 

 of scarifying the roof of the mouth is not to be resorted to, as it 

 does no good and may produce a serious complication of hemor- 

 rhage should the palatine artery be severed. 



The after-treatment. — Bleeding from the jugular is used 

 by some, but can be dispensed with in most cases unless there be 

 a succession of paroxysms. A full purge of aloes and calomel is 

 required, as in many cases the cause is intestinal. Then treat 

 symptomatically. 



Regulate the diet, give the necessary exercise, and use harness 

 that fits properly. 



