SPECIAL CLINICAL EXAMINATION. 77 



In regard to frequency we distinguish a slow pulse 

 (pulsus rants) and a rapid pulse (pulsus frequcns). 



The slow pulse (pulsus rants, bradycardia) is very un- 

 common. It most often accompanies brain diseases attended 

 by great depression (chronic and subacute hydrocephalus, 

 tumors in the brain), icterus gravis, and poisoning from alco- 

 hol or lead. In the horse at times it is seen in gastro- 

 intestinal affections with loss of appetite, probably due to 

 some alteration in the sympathetic nerve. 



Fig. 22. 



Slow, Sluggish Pulse of Horse. 

 Taken with Marey's Sphygmograph — Art transversa faciei. 



The fast pulse (pulsus frequcns, tachycardia,) is verv 

 common in disease. A very rapid pulse, though characteristic 

 of no special disease, is always a sign that the parenchyma 

 of the heart is affected, hence in severe diseases it is an index 

 to the heart's strength. Rarely in the horse does the pulse 

 frequency exceed 80 beats per minute; if it exceed 100, the 

 prognosis is unfavorable. In the ox a pulse of 100, and in 

 the dog one of 120-150 denotes severe illness. 



An abnormally accelerated pulse occurs : 

 1. In all severe diseases, especially when attended by 

 fever. The frequency of the pulse, however, does not always 

 bear the same relationship to the height of the temperature; 

 whether the pulse be accelerated or not depends upon the 

 fever's effect upon the heart, which differs with the disease 

 present. In contagious pleuropneumonia of the horse, septi- 

 cemia, anthrax, and severe inflammations of the bowels and 

 peritoneum, the pulse rate corresponds to the height of the 

 fever; in influenza and in strangles, the acceleration of pulse 

 is not marked, compared with the temperature. 



