LOCKED JAW. 81 



in constant motion from the alternate and violent action of tht 

 muscles that elevate and depress it. 



Constipation, and to an almost insurmountable degree, now ap- 

 pears. The abdominal muscles are so powerfully contracted, that 

 no portion of the contents of the abdomen can pass on and be 

 discharged. 



By degrees the spasm extends and becomes everywhere more 

 violent. The motion of the whole frame is lost, and the horse 

 stands fixed in the unnatural posture which he has assumed 

 The countenance becomes wilder and more haggard — its expres- 

 sion can never be effaced from the memory of him who cares 

 about the feelings of a brute. The violent cramp of a single 

 muscle, or set of muscles, makes the stoutest heart quail, and 

 draws forth the most piteous cries — what, then, must it be for 

 this torture to pervade the whole frame, and to continue, with 

 little respite, from day to day, and from week to week ! When 

 his attendant approaches and touches him, he scarcely moves , 

 but the despairing gaze, and the sudden acceleration of the 

 pulse, indicate what he feels and fears 



Tetanus is evidently an affection of the nerves, caused by an 

 injury to some one of them, and the effect of that injury has 

 spread to the origin of the nerve — the brain — and universal dis 

 eased action has followed. 



If the disease terminates fatally, it is usually from the sixth 

 to the eighth day. There are occasionally slight remissions in 

 the spasm, but not sufficiently to enable the animal to eat or to 

 drink. If these remissions return and increase in length, and 

 particularly if there is more relaxation of the lower jaw, there 

 is yet hope. If the horse recovers, it will be slowly, and he 

 will be left sadly weak, and a mere walking skeleton. 



On post-mortem examination the muscular fibre will exhibit 

 sufficient proof of the labor which has been exacted from it. 

 The muscles will appear as if they had been macerated — their 

 texture will be softened, and they will be torn with the greatest 

 ease. The lungs will, in the majority of cases, be highly in- 

 flamed, for they have been laboring long and painfu ly, to fur- 

 nish arterial blood in sufficient quantity to support this great 

 expenditure of animal power. The stomach will contain patches 

 of inflammation, but the intestines, in most cases, will not ex- 

 hibit much departure from the hue of health. The examination 

 of the brain will be altogether unsatisfactory. There may be 

 slight injection of some of the membranes, but, in the majority 

 of cases, there will not be any morbid change worthy of record . 



Tetanus most usually occurs from injvifies to some nervous 

 fibre of the foot — sometimes from a prick in shoeing. It is 

 also connected with docking, nicking and castration (q. v.) 

 6 cl 



