60 The Ailments of Horses, 



Navicular disease. — This is an in- 

 curable malady affecting the navicular 

 bone, its cartilage, bursa, synovial mem- 

 brane, and tendon gliding over its surface. 



It is a very common complaint, and 

 almost always confined to one or both 

 fore feet. 



Horses thus affected are vulgarly termed 

 " grogs," and their action is spoken of as 

 being " groggy." 



The short catlike step is very cha- 

 racteristic of the disease, though this is 

 not so evident if the malady is confined 

 to one limb. 



In order to destroy the pain arising 

 from this affection, an operation known 

 as unnerving (neurectomy) is frequently 

 practised. This oj^eration in no way does 

 away with the disease— merely the pain. 



An unwary purchaser may quite easily 

 be taken in by having an unnerved horse 

 palmed off as a sound animal. 



So far as the purchaser is concerned, 

 such an animal is worthless, though we 

 do not say useless for work. 



The nerves are divided in the hollow 

 just above the fetlock joint, so that careful 

 scrutiny at this seat is necessary. The 

 presence of a slight scar here points to 

 this operation having been performed. 

 However, it is quite easy to confirm one's 

 opinion by pricking the foot below this 

 part. It (the animal) does not respond 

 to the stimulus thus applied. In other 

 words, sensation is lost after the nerve 

 has been cut and a j^ortion taken away. 



Symptoms. — Pointing of the foot (shoe 



