554 NERVOUS DISEASES. 



in the same mobs at the same time and under precisely similar 

 circumstances, it is evident that they are only modifications of the 

 same disease, and are due to the same cause or causes. 



" The first indication of the disease is an alteration in the 

 animal's gait. There is a dragging in all the limbs and frequent 

 stumbling ; the hind fetlocks knuckle over, and the thighs have a 

 thin wasted appearance, when viewed from behind. The horse 

 stands and moves in a crouching manner ; the hind quarters being 

 carried low, and all the joints of the hind limbs flexed. In some 

 cases the muscles of the shoulders also become atrophied. If the 

 horse is made to move any distance, he breaks out into a perspira- 

 tion. As in the other forms of the disease, the attack is usually 

 very sudden, and the sudden wasting of the muscles is not so easily 

 accounted for. If the horse should fall or lie down, he may be 

 unable to rise, and, if not properly attended to, death usually takes 

 place about the third or fourth day. When down, the animal 

 struggles violently, and often paws great holes in the ground, using 

 the hind legs as well as the fore ones, thus showing that the in- 

 ability to rise is not due to paralysis of the hind extremities, as 

 some suppose ; for if raised by means of slings, he can both stand 

 and walk ; and if the horse has not lain too long before assistance 

 is given, and is properly attended to afterwards, he usually re- 

 covers. When standing, the weight is frequently shifted from one 

 hind leg to the other, and the limb that is being relieved is sud- 

 denly snatched up, though not to the same extent as in the other 

 two forms of the disease. The crouching attitude with the 

 knuckling over of the hind fetlocks is maintained in standing, and 

 the animal is often wet from perspiration as if from pain. The 

 fetlock joints are often hot, tender and swollen. The appetite is 

 generally good in all forms of the disease, and even when down 

 in the last-described form, the horse will often eat up to the last. 

 Beyond perhaps a little constipation, the bowels remain imaffected, 

 and the urine is voided in the usual quantities without difficulty. 

 The pulse is invariably quick in all forms of the disease, is often 

 weak, and sometimes both irregular and intermittent, showing that 

 the action of the heart is disturbed. The breathing is not mate- 

 rially affected, except when the horse has been disturbed, or is 

 suffering more than usual pain. The internal temperature did 

 not vary more than one or two degrees beyond the normal, in any 

 of the cases that came under my notice. The mucous membranes 

 are usually normal, though sometimes there may be a slight yel- 

 lowish tinge. The first sign of recovery in this form is a gradual 

 straightening of the hind fetlocks, and disappearance of the pain 

 and nervousness; but the muscles of the thighs and shoulders are 

 slow to regain their ordinary form" (Kendall)^ 



