DISEASES OF NERVOUS SYSTEM 



CONGESTION OF BRAIN (HYPEREMIA OF BRAIN) 



Causes. — This is a condition which may be produced in hogs 

 in hot weather by overheating due to handhng. Hyperemia of 

 the brain is especially likely to occur where animals are run and 

 chased over feed lots in an effort to catch and restrain them for 

 purposes of injecting serum, castration, ringing, and similar pur- 

 poses. The condition is unusually liable to be developed in fat 

 animals, as these stand handling very poorly as a rule. 



Symptoms. — The principal symptoms are dulness, stupidity, 

 and an awkward gait. There is also considerable evidence of ex- 

 haustion as a rule. The animal breathes rapidly and the pulse 

 will be found to be rapid and feeble. There may be a period of 

 excitement in which the animal is very restless, and this will be 

 followed by the period of depression. 



Treatment in these cases consists essentially in keeping the 

 animals quiet. Get them out of the sun into a cool place, and leave 

 them alone, undisturbed. The condition is only a temporary one, 

 and with rest and quiet entire recovery takes place in two or three 

 hours. 



INFLAMMATION OF BRAIN (BRAIN FEVER) 

 In congestion of the brain there is simply a dilatation and over- 

 filling of the blood-vessels of the organ. In inflammation of the 

 brain the condition is a more serious one, and there is a genuine 

 involvement of the brain tissue. Brain fever, as the condition is 

 commonly called, is rather uncommon in the hog, but may be seen 

 occasionally in run-down animals or in hogs that are suffering from 

 some of the acute infectious diseases, such as pneumonia or hog- 

 cholera. 



Brain fever may also occur in fat animals as a result of over- 

 exercise, sunstroke, or blows on the head. In animals that feed in 

 the same yards with cattle the condition occasionally develops as 



