PARASITOLOGY. 131 
From this coagulum there may break loose at differ- 
ent times, emboli which may produce more or less 
serious results depending on the size of the embolus 
and the location of the embolism. There will be 
ischemia of that portion of the intestine to which the 
vessel is disturbed, and paralysis of that portion of 
the digestive tube. The secretions are suspended and 
thrombi-embolic colic results. 
The ischemic portion, at first pale, now becomes 
dark red, due to the passive congestion. The mucous 
membrane appears swollen and hemorrhagic infarction 
occurs. A serous exudate may be present and the 
organ appears increased in size. This condition fa- 
vors infection from the bowel and more serious results 
may follow. 
THROMBO-EMBOLIC COLIC. 
Fermentation of the ingesta of this now paralyzed 
part of the digestive tube may take place. The horse 
shows colicky pains, lies down and gets up frequently, 
perspires first in spots later may be covered with per- 
spiration. If rupture of the aneurism takes place 
during the attack of colic the animal will be noted to 
sit up on his haunches, knuckles over in its fetlocks. 
There will be blanched or pale visible mucous mem- 
branes. The extremities are cold. The pulse is weak 
and thready. If the aneurism be located in the pos- 
terior aorta this vessel is more likely to rupture be- 
cause of the high blood pressure in it. 
Bollinger records fifteen ruptured aneurisms as hav- 
ing taken place into the peritoneal sac and three into 
the intestines. 
