DISEASES OF THE HEART AND ORGANS 

 OF CIRCULATION. 



Susceptibility in different genera. Reasons for partial immunity of the 

 quadruped, special and general causes in quadrupeds, violent, forced work, 

 fatty degeneration, swallowing of pointed metallic bodies, difiBcult diagno- 

 sis in the animal. Position of the heart in the horse, ox, sheep, pig, car- 

 uivora, birds. Structure of the heart as a pump. Results of imperfect 

 structure or action. Heart-walls. Table of size of the heart. Capacity. 

 Weight. Pulse in each healthy genus, according to age, size, environment, 

 temperament, proximity to parturition. Morbid conditions of the pulse, 

 frequent, slow, quick, tardy, full, strong, weak, feeble, indistinct, small, 

 hard, wiry, thready, oppressed, leaping and receding, intermittent, unequal, 

 irregular, anaemic, venous. Percussion. Palpitation. Ausculation. Healthy 

 sounds. Morbid sounds, in unusual place, force, intensity, rythm, repeti- 

 tion of 1st sound, of 2nd sound. Murmurs, synchronance with given stages 

 of heart movement, their significance, pericardial murmur. General symp- 

 toms of heart disease, cold extremities, passive congestions, dropsies of 

 limbs, etc., shortness of breath, venous pulse, vertigo, dulness, sluggish- 

 ness, corpulence. 



The lower animals are perhaps less subject to heart disease than 

 mankind, but the comparative immunity generally assumed for 

 them is far from being a real one. The horizontal position of the 

 quadruped largely obviates that special tax upon the heait de- 

 manded by the erect position of man, and especially by the elevated 

 place given to his more ample and vascular brain. Animals too 

 are comparatively free from those mental and moral influences 

 which so largely affect the regularity of the circulation in the 

 human subject. But on the other hand many physical causes of 

 heart disea.se affect the lower creation equally with their lord, 

 while some undoubtedly operate with special force on the brute. 

 All animals are subject to diseases of the heart as of other internal 

 organs, from exposure ; this organ is occasionally involved from 

 its contiguity with other diseased structures or from interdepend- 

 ence of function as we have already seen in certain diseases of 

 the lungs (congestion, brokenwind, etc.); the tendency to heart 

 disease frequently runs in a particular family of animals, espe- 

 cially with the rheumatic constitution, which is transmitted from 

 parent to offspring as surely as the color of the skin the turn of 



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