INFLAMMATION OF THE AORTA. AORTITIS. 



Horse. Causes. This has been traced to undue stretching of 

 the vessel, as in .slipping of the hind feet backward, or kicking out 

 and very high (Goubaux), sudden falls, sprains of the back (Sab- 

 ourine), penetrating wounds (Biirmann), irregular strangles with 

 abscess, rheumatism (lyiard), endocarditis extending to the vessel 

 (Trasbot), atheroma (Axe), and the larva of sclerostoma equi- 

 num. 



Lesions. These are essentially those already described under ar- 

 teritis. The seat of aortitis is usually a limited section of the vessel, 

 and though in case of sclerostoma it may be very extended, yet as 

 a rule it is confined to the lumbar region, near the points of origin 

 of the anterior and posterior mesenteric arteries. The secondary 

 lesions may be very varied ; embolism of one renal artery with 

 atrophy of the corresponding kidney, and enlargement of the 

 other renal vessel and hypertrophy of its kidney ; embolism of 

 the cceliac axis, or of the anterior or posterior mesenteric artery, 

 with violent, perhaps fatal colic ; embolism of the external iliac 

 artery or its branches with intermittent paresis of "the muscles of 

 that limb occurring under exercise ; embolism of the hepatic or 

 renal artery with consequent dropsy ; hypertrophy of the left 

 ventricle through the demand for more force to overcome the 

 obstruction in the inflamed artery. 



Symptoms are very indefinite, unless plugging of the iliacs and 

 their branches leads to intermittent lameness and even then the 

 aortitis would only be an inference, but by no means proved. 



Cattle. Causes. Tuberculosis is the most common cause, the 

 intima of the aorta showing small nodular elevations like a small 

 pea, with tubercle bacilli and caseated centre, or ulcerations, or 

 calcifications. The vegetations may extend into vessels originat- 

 ing from the aorta, or may block the openings of such trunks and 

 give rise to various disorders. 



Dog. Causes. Aortitis has been especially noticed as the result 

 of parasitism and particularly of the spiroptera sanguinolenta or less 

 frequently the filaria immitis. There may be disease of the 

 tricuspid or aortic valves, and vertigo or syncope may result. 



Prevention. Treatment is out of the question. Prevention 

 would be possible in the case of the parasitic cases by keeping the 

 horse's intestines free from the sclerostoma, and by the removal, 

 from kennels and localities, of dogs suffering from the blood 

 strongyle and filaria. 488 



