226 DISEASES OF THE HORSE. 



horsemen as " thumps." This condition may be distinguished from 

 violent beating of the heart by feeling the pulse beat at the angle of 

 the jaw, and at the same time watching the jerking movement of the 

 body, when it will be discovered that the two bear no relation to each 

 other. (See " Palpitation of the heart," p. 259.) 



SpasTih of the thigh, or crarrvp of a hind limh. — This is frequently 

 witnessed in horses that stand on sloping plank floors — generally in 

 cold weather — or it may come on soon after severe exercise. It is 

 probably due to an irritation of the nerves of the thigh. In cramps 

 of the hind leg the limb becomes perfectly rigid, and attempts to flex 

 are unsuccessful; the animal stands on the affected limb, but is 

 unable to move it; it is unnaturally cold; it does not, however, 

 appear to cause much suffering unless attempts are made to change 

 position. This cramp may be of short duration — a few minutes — or 

 it may persist for several days. This condition is often taken for a 

 dislocation of the stifle joint. In the latter the foot is extended back- 

 ward, and the horse is unable to advance it, but drags the limb. An 

 examination of the joint also reveals a change in form. Spasms 

 may affect the eyelids, by closure or by retraction. Spasm of the 

 sterno-maxillaris muscle has been witnessesd, and the animal was 

 unable to close the jaws until the mu^scle became relaxed. 



T7'eat7nent of spasms. — An anodyne liniment, composed of chloro- 

 form 1 part and soap liniment 4 parts, applied to cramped muscles 

 will usually cause relaxation. This may be used when single exter- 

 nal muscles are affected. In spasms of the glottis, inhalation of sul- 

 phuric ether will give quick relief. In spasm of the diaphragm, rest 

 and the administration of half an ounce of chloroform in 3 ounces of 

 whisky, with a pint of water added, will generally suffice to bring 

 relief, or if this fails give 5 grains of sulphate of morphia by hypo- 

 dermic injection. If spasms result from organic disease of the nerv- 

 ous system, the latter should receive such treatment as its character 

 demands. In cramp of the leg, compulsory movement usually causes 

 relaxation very quickly; therefore the animal should be led out of 

 the stable and be forced to run or trot. Sudden, nervous excitement 

 caused by a crack of the whip or smart blow will often bring about 

 immediate relief. Should this fail, the anodyne liniment may be 

 used along the inside of the thigh, and chloroform, ether, or lauda- 

 num given internally. An ounce of the chloral hydrate will cer- 

 tainly relieve the spasm when given internally, but the cramp may 

 return soon after the effect has passed off, which in many cases it 

 does very quickly. 



Convulsions. — Although there is no disease of the nervous system 

 which can be properly termed convulsive, or justify the use of the 

 word convulsion to indicate any particular disease, yet it is often 

 such a prominent symptom that a few words may not be out of place. 



