434- Hypertrophy, or enlargement of the heart, may be considered 

 as follows — 



A. — Hypertrophy without dilatation, when the walls oi the 

 heart are thickened, but the capacity of the cavities 

 remain unchanged. 



B. — Hypertrophy with dilatation, when the cavities are 

 enlarged, as well as the walls being thickened, and 

 when the heart is enlarged throughout, with the 

 walls very thin, flabby, and pale, and the cavities 

 dilated. 



435. The heart may also become atrophied or attenuated, when not 

 only is the organ itself nnich smaller than normal, but the walls and 

 cavities are also diminished. 



436. When a horse is noticed, while pulling a load up a hill, to stop 

 every few steps, almost breathless ; to have dilated nostrils and staring 

 eyes, and the heart beating with a thumping sound loud enough to be 

 heard, or fluttering with an irregular sound, while the pulse is scarcely 

 perceptible, and there is a waving flow in the jugular vein up the 

 neck ; it may be then set down that some heart complication is present. 

 A slight canter will produce similar symptoms with an affected horse. 



•Owing to the thick walls of the sides and front of the chest of all the 

 domestic animals — with the exceptions of the dog and cat — the sounds 

 of the heart are very difficult to define, thus making it almost impossible 

 to distinguish one disease from another by sounding. The best mode 

 of detecting the sounds of the heart of the horse is to lift the near fore 

 leg, pull it well forward, and apply the ear to the side behind the 

 elbow. Treatment for a diseased heart is of little avail ; but the 

 horse may live a long time, and do a lot of farm work, so long as it is 

 slow and easy. As the legs are inclined to swell, preparations of iron, 

 digitalis, and potash, will assist materially in giving tone to the animal 

 (see Appendix). 



437. In the examination of horses as to soundness, it is of the 

 greatest importance to note the state of the pulse, the sounds of the 



