198 BUliEAU OF ANIMAL INDUSTRY. 



merely a functional affection, and in a .sligfht or moderate degree 

 involves no immediate danger. Extreme engorgement, on the con- 

 trary, ma}' be followed by rupture of previously weakened arteries 

 and capillaries and cause immediate death, designated then as a stroke 

 of apoplex}'. 



Symjjtoms. — Congestion of the brain is usually sudden in its mani- 

 festation and of short duration. The animal ma}' stop very suddenly 

 and shake his head or stand quietly braced on his legs, then stagger, 

 make a plunge, and fall. The eyes arc staring, breathing hurried and 

 stertorous, and the nostrils widely dilated. This may be followed by 

 coma, violent convulsive movements, and death. Generally, however, 

 the animal gains relief in a short time, but he may remain weak and 

 giddy for several days. If it is due to organic change of the heart or 

 to disease of the blood vessels in the brain, then the symptoms may be 

 of slow development manifested by drowsiness, dimness or imperfect 

 vision, difficulty in voluntary movements, diminished sensibility of the 

 skin, loss of consciousness, delirium, and death. In milder cases effu- 

 sion may take place in the arachnoid spaces and ventricles of the brain, 

 followed by paralysis and other complications. 



Pathology. — In congestion of the brain the cerebral vessels are loaded 

 with blood, and the venous sinuses distended to an extreme degree, 

 and the pressure exerted upon the brain constitutes actual compres- 

 sion, giving rise to the symptoms just mentioned. On postmortem 

 examinations this engorgement is found universal throughout the 

 'brain and its membranes, which serves to distinguish it from inflam- 

 mations of these structures, in which the engorgements are confined 

 more or less to circumscribed portions. A prolonged congestion may, 

 however, lead to active inflammation, and in that case we will find 

 serous and plastic exudations in the cavities of the brain. In addition 

 to the intensely engorged condition of the vessels we find the gray 

 matter of the brain redder in color than natural. In cases where 

 several attacks have occurred the blood vessels are often found perma- 

 nently dilated. 



Treatment. — Prompt removal of all mechanical obstructions to the 

 circulation. If it is due to venous obstruction by too tight a collar, the 

 loosening of the collar will give immediate relief. The horse should 

 be bled freely from the jugular vein. If due to tumors or abscesses, 

 a surgical operation becomes necessary to afford relief. To revive the 

 animal if he becomes partially or totally unconscious, cold water should 

 be dashed on the head. Give a purge of Glauber's salts. If the limbs 

 are cold, tincture of capsicum or strong mustard water should be 

 applied to them. If symptoms of paralysis remain after two or three 

 days, an active cathartic and iodide of potassa will be indicated, to 

 be given as prescribed for inflammation of the brain. 



Pi'evention. — Well-adjusted collar, with strap running from the col- 



