232 DISEASES OF THE HORSE. 



further transmission. If the animal manifests symptoms of im- 

 provement, the changes usually are slow and steady until he feels 

 apparently as well as ever, eats Avell, and moves freely in his stall 

 or yard. A\Tien he is taken out, however, the seeming strength often 

 proves deceptive, as he may quickly weaken if urged into a fast gait, 

 the breathing becomes quickened with a double flank movement as 

 in heaves, and all the former symptoms reappear in a modified degree. 

 An examination at this stage may reveal valvular insufficiency, car- 

 diac hypertrophy, or pulmonary engorgement. 



In fatal cases of endocarditis death often occurs about the fourth 

 day, from the formation of heart clot or too great embarrassment of 

 the circulation. Endocarditis may be suspected in all cases where 

 plain sA'mptoms of cardiac affection are manifested in animals af- 

 fected with influenza, rheumatism, or any disease in which the blood 

 may convey septic matter. 



Acute endocardial inflammation may be distinguished from pleu- 

 ritis by the absence of any friction murmur, absence of pain when the 

 chest wall is percussed, and the absence of effusion in the cavity of 

 the chest. It may be distinguished from pericarditis by the absence 

 of the friction sounds and want of an enlarged area of dullness on 

 percussion. 



Treatment. — The objects to be attained by treatment will be to 

 remove or mitigate as much as possible the cause inducing the disease ; 

 to find a medicine which will lessen the irritability of the heart with- 

 out weakening it ; and, last, to maintain a free urinary secretion and 

 prevent exudation and hypertrophy. So long as there is an increase 

 of temperature, with some degree of scantiness of the urine, it may be 

 safe to believe that there is some degree of inflammatory action exist- 

 ing in the cardiac structures, and as long as any evidence of inflam- 

 matory action remains, however moderate in degree, there is a ten- 

 dency to increase or hypertrophy of the connective tissue of the heart 

 or valves, thereby rendering it almost certain that the structural 

 changes will become permanent unless counteracted by persistent 

 treatment and complete rest. 



The tincture of digitalis, in 20-drop doses, repeated ever}?^ hour, is 

 perhaps the most reliable agent we know to control the irritability of 

 the heart, and this also has a decided influence upon the urinary 

 secretion. After the desired impression upon the heart is obtained 

 the dose may be repeated every two or three hours, or as the case may 

 demand. Tincture of strophanthus, in 2-dram doses, will quiet the 

 tumultuous action of the heart in some cases where the digitalis fails. 

 Bleeding, blistering, and stimulating applications to the chest should 

 be avoided. They serve to irritate the animal and can do no possible 

 good. Chlorate of potassa, in 2-dram doses, may be given in the 

 drinking water every four hours for the first five or six days, and then 



