248 DISEASES OF THE BRAIN 



back the horse is futile. The heart action is slow, the pulse 

 in some casesi dropping to 20 or 30, although it retains its 

 normal softness. The symptoms of depression, appearing 

 from time to time, are due to a rise of intracranial pres- 

 sure. Periods of excitement may occur which cause the 

 animal to show symptoms as in the stage of excitement 

 in acute inflammation of the brain. The appetite of the 

 "dummy" is often impaired and the prehension of food 

 unphysiological. Eating is quite frequently interrupted, the 

 animal apparently forgetting for the moment that it is at a 

 meal. In drinking the head is often projected up to the eyes 

 in water; in some instances the animal tries to 'eat" rather 

 than drink the water. As noted these sjinptoms are usually 

 emphasized by exercise until the animal is in a profuse sweat. 

 Occasionally symptoms of vertigo and syncope occur. The 

 skin reflexes (snapping the forehead, poking a finger in the 

 ear, treading upon the coronet) are either diminished or may 

 in some cases be exaggerated. In driving a "dummy" some- 

 times the animal tends to go to the left or right of the road 

 notwithstanding the effort of the driver to prevent it. The 

 gait is often abnormal, the animal walking as if in water, with 

 a high wading movement of the forelimbs, or, on the other 

 hand, it may frequently stumble, setting its feet down in an 

 uncertain fashion. 



Course. — ^The course is chronic and accompanied by many 

 exacerbations and remissions. The animal may live for many 

 months or even years showing improvement in cold and 

 becoming worse in warm weather. In exceptional cases it 

 may even refuse to eat and die of starvation. It is remark- 

 able how often the condition as to flesh is retained notwith- 

 standing a very variable appetite and the relatively small 

 quantity of food consumed. 



Prognosis. — ^The prognosis is bad as far as producing heal- 

 ing is concerned. However, many "dmnmies" can render 

 service at slow work and especially during cool weather for 

 months or even years. In time, however, through gradual 

 mental and locomotor disturbances, their usefulness ceases, 

 and eventually they are destroyed. 



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