THBOMBO-EMBOLIC COLICS. 



163 



friable, and puriform. In the centre of this clot we find the 

 Strongylus armata (the average number of parasites is nine, accord- 

 ing to Bollinger), which is the specific agent in these grave altera- 

 tions; chronic traumatic endarteritis causes them by producing in 

 its turn thrombus and aneurism. 



Verminous aneurism in its relation to colics. Aneurism 

 not only occasions nutritive troubles in the intestinal walls and 

 favors the development of colic through its hindrance to the course 

 of the blood, but the horse which is affected by it is constantly 

 exposed to a triple danger: at times the thrombus ends by ob- 

 structing the opening of the great mesenteric artery, though this is 

 rare; at other times it is prolonged more or less into one of the 

 branches of this trunk ; then, again, we see a part of the clot 

 becoming detached from the principal mass, carried along by the 

 blood, and arrested in an intestinal artery which it completely 

 occludes. In all these cases, when the collateral circulation is not 

 established in a sufficient degree to keep up the blood circulation 

 in the anemic territory, we soon observe grave disorders, which 

 have been studied and experimented upon by Virchow, Colin, 

 Panum, Cohnheim, Litten, and others. The arterial occlusion 

 causes stagnation and reflex of the venous blood, which is rapidly 

 accompanied by a sero-bloody transudation in the intestinal tube 

 and in the substances of its walls (sero-hemorrhagic infarct). This 

 infiltration immediately causes paralysis of the intestine, and this 

 in turn leads to stagnation of the intestinal contents, which fer- 

 ment and give off an abundance of gases. It may also cause 

 volvulus and invagination, accidents due to the activity of move- 

 ment of the healthy intestinal loops, which pass into the interior 

 of the paralyzed portion, or envelop it. We have frequently ob- 

 served rotation of the left portion of the large colon upon its axis 

 — that is to say, of the free portion of this organ. 'Now, of the dif- 

 ferent intestinal compartments, it is here that emboli and thrombi are 

 most frequently observed ; we must therefore, it would seem, admit 

 that arterial anemia leads to change of relations of the intestine 

 by the disturbances which it occasions. However, we do not 

 think that rotation of the colon can be produced simply by the 

 violence of the movements acting in the neighboring intestinal 

 divisions. 



Among the other complications of paralysis of the intestine are 

 to be mentioned ruptures of this organ, of the stomach and dia- 



