304 THE PULSE. 



THE PULSE 



Is caused by the yielding of the coats of the artery to the g-ush of blood 

 forced into it hy the contraction of the heart. It is a very useful assistant 

 to the practitioner of human medicine, but much more so to the veterinary 

 surgeon, whose patients cannot describe either the seat or degree of ail- 

 ment or pain. The number of pulsations in any artery will give the 

 number of the beatings of the heart, and so express the irritation of that 

 organ, and of the frame generally. In a state of health, the heart beats in 

 a horse from about thirty-two to thirty-six times in a minute. This is said 

 to be the standard pulse — the pulse of health. It varies sing-ularly little 

 in horses of the same size and breed, and where it beats naturally there 

 can be little materially wrong. The most convenient place to feel the 

 pulse is at the lower jaw (p. 199) a little behind the spot where the sub- 

 maxillary artery and vein and the parotid duct come from under the jaw. 

 There the number of pulsations will be easily counted, and the character 

 of the pulse, a matter of fully equal importance, will be clearly ascertained. 

 Many horsemen put the hand to the side. They can certainly count the 

 pulse there, but they can do nothing more. We must be able to press the 

 artery against some hard body, as the jawbone, in order to ascertain the 

 manner in which the blood flows through it, and the quantity that 

 flows. 



Wlien the pulse reaches fifty or fifty-five, some degree of fever may be 

 apprehended, and proper precaution should be taken ; seventy or seventy- 

 five will indicate a dangerous state, and put the owner and the sui'geon 

 not a little on the alert. Few horses long survive a pulse of one hun- 

 dred, for by this excessive action the enei'gies of nature are speedily 

 worn out. 



Some things, however, should be taken into account in fonning our con- 

 clusion from the frequency of the pulse. Exercise, a warm stable, and 

 fear will wonderfully increase the number of pulsations. In the preg- 

 nant condition of the mare the pulse will also be found increased. 



When a careless brutal fellow goes up to a horse, and speaks hastily to 

 him, and handles him roughly, he adds ten beats per minute to the pulse, 

 and will often be misled in the opinion he may form of the state of the 

 animal. A judicious person will approach the patient gently, and pat and 

 soothe him, and even then probably the circulation will be a little dis- 

 tui'bed. He should take the additional precaution of noting the number 

 and quality of the pulse a second time before he leaves the animal. 



If a quick pulse indicate irritation and fever, a slow pulse 'svill likcwdse 

 characterise diseases of an opposite description. It accompanies the sleepy 

 stao'e of staggers, and every malady connected with deficiency of nervous 

 energy. 



The heart may not only be excited to more fi-equent but also to more 

 violent action. It may contract more powerfully upon the blood, which 

 will be driven with greater force through the arteries, and the expansion 

 of the vessels will be greater and more sudden. Then we have the hard 

 pulse, the sure indicator of considerable fever. 



Sometimes the pulse may be hard and jerking, arid yet small : the 

 stream though forcible is not great. The heart is so irritable that it con- 

 tracts before the ventricle is properly filled. The practitioner knows that 

 this indicates a dangerous state of disease. It is an almost invariable 

 accompaniment of inflammation of the boAvels. 



A iceah pulse, when the artei'ial stream flows slowly, is caused by the 

 feeble action of the heart. It is the reverse of fever, and expressive of 

 debility. 



