244 DISEASES OF THE HOKSE. 



intestinal canal, serous or bloody exudation in its walls, which leads 

 to paralysis of the intestine and resultant colicky symptoms. 



Treatment. — The only treatment advisable is to extirpate or ligate 

 the tumor above and below. 



RUPTURE OF AN ARTERY. 



Endarteritis, with its subsequent changes in the walls of arteries, is 

 the primary cause of rupture in the majority of instances. The rup- 

 ture may be partial, involving only one or two coats, and will then 

 form an aneurism. If complete, it may produce death when it in- 

 volves a large vessel, especially if it is situated in one of the large 

 cavities permitting an excessive escape of blood. Rupture may be 

 produced by mechanical violence or accident. 



Symptoms. — In fatal rupture associated with profuse bleeding, the 

 animal becomes weak, the visible mucous membranes become blanched, 

 the breathing hurried or gasping, pupils dilated, staggering in gait, 

 syncope, death. When the hemorrhage is limited, the symptoms may 

 not become noticeable ; if it is near the surface of the body a round or 

 diffuse swelling or tumor may form, constituting a hygroma. If the 

 rupture is associated with an external wound the bleeding artery 

 should be ligated, or where a bandage is applicable, pressure may be 

 applied by tight bandaging. As a secondary result of rupture of an 

 artery we may have formation of abscess, gangrene of a part, etc. 



Treatment. — When rupture of a deep-seated artery is suspected, 

 large doses of fluid extract of ergot may be given to produce contrac- 

 tion of the blood vessels. Tannin and iron are also useful. The 

 animal should be allowed to have as much water as he desires. After- 

 wards stimulants and nourishing food are indicated. 



THROMBUS AND EMBOLISM. 



By thrombosis is generally understood the partial or complete clo- 

 sure of a vessel by a morbid product developed at the site of the 

 obstruction. The coagulum, which is usually fibrinous, is known as 

 a thrombus. The term embolism designates an obstruction caused by 

 any body detached and transported from the interior of the heart or 

 of some vessel. Thrombi occur as the result of an injury to the wall 

 of the vessel or may follow its compression or dilatation; they may 

 result from some alteration of the wall of the vessel by disease or 

 by the retardation of the circulation. These formations may occur 

 during life, in the heart, arteries, veins, or in the portal system. 

 When a portion of fibrin coagulates in one of the arteries and is car- 

 ried along by the circulation, it will be arrested, of course, in the 

 capillaries, if not before; when in the veins, it may not be stopped 

 until it reaches the lungs; and when in the portal system, the capil- 

 laries of the liver will prevent its further progress. The formation of 



