DISEASES OF HORSES 369 



may sometimes be heard by placing the ear over the heart on the 

 left side of the chest. 



Treatment. When the pulse is irregular or irritable, tonics, 

 such as preparations of iron, gentian, and ginger, may be given. 

 When the action of the heart is jerking or violent, 20 to 30 drop 

 doses of tincture of digitalis or of veratrum viride may be given 

 until these symptoms abate. As the disease nearly always is the 

 result of endocarditis, the iodide of potassa and general tonics, 

 sometimes stimulants, when general debility supervenes, may be 

 of temporary benefit. Very few animals recover or remain useful 

 for any length of time after once marked organic changes have 

 taken place in the valvular structure of the heart. 



ADVENTITIOUS GROWTHS IN THE HEART. 



Fibrous, cartilaginous, and bony formations have been ob- 

 served in some rare instances in the muscular tissue. Isolated cal- 

 careous masses have sometimes been embedded in the cardiac walls. 

 Fibrinous coagula and polypous concretions may be found in the 

 cavities of the heart. The former consist of coagulated fibrin, sep- 

 arated from the mass of blood, of a whitish or yellowish white color, 

 translucent, of a jellylike consistence, and having a nucleus in the 

 center. They may slightly adhere to the surface of the cavity, 

 from which they can easily be separated without altering the struc- 

 ture of the endocardium. They probably result from an excess of 

 coagulability of fibrin, which is produced by an organization of the 

 lymph during exudation. They are usually found in the right 

 auricle and ventricle. 



Symptoms. These are frequently uncertain; they may, how- 

 ever, be suspected when the action of the heart suddenly becomes 

 embarrassed with irregular and confused pulsations, great difficulty 

 of breathing, and the usual signs dependent upon the imperfect ar- 

 terialization of the blood. Stimulants, whisky, or carbonate of am- 

 monia may be of service. 



PALPITATION OF THE HEART. 



This is a tumultuous and usually irregular beating of the heart. 

 It may be due to a variety of causes, both functional and organic. 

 It may occur as a result of indigestion, fright, increased nervous- 

 ness, sudden excitement, excessive speeding, etc. 



Symptoms. The heart may act with such violence that each 

 beat may jar the whole body of the animal; very commonly it may 

 be heard at a short distance away from the animal. It can usually 

 be traced very readily to the exciting cause, which we may be able 

 to avoid or overcome in the future and thereby obviate subsequent 

 attacks. Rest, a mild stimulant, or a dose or two of tincture of digi- 

 talis or opium will generally give prompt relief. When it is due to 

 organic impairment of the heart it must be regarded as a symptom, 

 not as a matter of primary specific treatment. 



SYNCOPE, OR FAINTING. 



Actual fainting rarely occurs among horses. It may, however, 

 be induced by a rapid and great loss of blood, pain of great in- 



