THE NERVOUS SYSTEM 365 



fairly well. Two-drachm doses of bromide of potassium, and 

 2 scruples of exsiccated sulphate of iron, given daily, followed up 

 with 1 -drachm doses of nux vomica, are very beneficial in such 

 cases. 



600. Shivering, although varying very much in degree, is some- 

 times readily noticed when the animal is standing in the stable, for, 

 on being made to move over from one side of the stall to the other, 

 the tail is suddenly jerked upwards and quivers, while the great 

 muscles of the thighs and quarters assume a rigid condition. On 

 putting the animal back, the hind-legs are moved in a stiff, straddling 

 manner, the animal backing with great difficulty. Horses thus 

 affected, when in the stall, always stand stretched out, with the hind- 

 legs back, and the point of the toe in the channel. 



601. Stringhalt is known by a sudden, spasmodic clicking up of 

 one or both hind-legs. It is, at times, seen when the animal is turned 

 quickly round, or if made to stand perfectly still, and then walked 

 smartly forward, when it is noticed at the first step. It is also exhibited 

 when forcibly backed or excited, but slight cases are difficult to detect, 

 as the clicking action is not always noticeable, the horse only showing 

 the peculiar action at irregular intervals. Cases have been known 

 where horses have been bred and worked on the farm until they were 

 five or six years old ; they have then been 'made up,' and sold at 

 public auctions without any unsoundness being manifested, but after 

 having been put on rail, and taken out at the end of the journey, 

 they have been found to be confirmed cases of stringhalt or shivers. 

 Whether this is due to fright on being railed for the first time, or 

 from the jerking they get in the horse-box while shunting at the 

 stations, is questionable, but it is a matter of great moment to both 

 buyer and seller. It is needless to add that animals affected with 

 these nervous disorders are classed as unsound ; yet they can work 

 for years, and carry very heavy loads forward, but have great diffi- 

 culty in backing. 



602. Dogs also suffer very much from chorea, it being a frequent 

 sequel to distemper (par. 532). In such cases Fellows' compound 



