CHAP. n. NAVICULAR DISEASE. ^ 573 



blood-stained patch appears. If the discoloration is near to the 

 surface the injury is an old one and may be of no account, but if it is 

 deep down, near to the quick or sensitive sole, it is of recent 

 occurrence and is invariably attended with lameness. 



Horses having flat spreading feet with low weak heels are specially 

 liable to corns, but under certain circumstances all descriptions of feet 

 may suffer. For the most part they are to be referred to bad shoeing, 

 but bruises are sometimes inflicted accidentally by the lodgment of 

 stones between the shoe and the bars or frog. 



Symptoms. Corns give rise to lameness in proportion to the severity 

 and extent of the injury. In progression the foot is brought to the 

 ground with an inclination towards the outer side, so that the weight is 

 removed from the injured part. The inner quarter of the hoof is hot, 

 and in severe cases swelling of the pastern and fetlock may appear by 

 extension of the inflammation upwards. This sometimes leads to the 

 error of attributing the lameness to sprain of the enlarged joints. In 

 severe and neglected cases an abscess may form in the foot and " break 

 out " at the coronet, giving rise to what is termed a quittor. 



Treatment. If the lameness is severe the corn must be well pared 

 that is, the blood-stained horn must be removed nearly down to the 

 quick, and if matter has accumulated it must be let out. The foot 

 should then be placed in a pail of hot water for an hour, and afterwards 

 transferred to a warm bran poultice. The latter should be changed 

 two or three times a day, and continued until the lameness passes 

 away. To complete the cure it may be necessary to apply a blister 

 over the coronet and cold swabs to the foot, or to use a three-quarter shoe. 



Horses subject to corns require careful shoeing, and may be allowed 

 to wear leather soles with advantage. 



NAVICULAR DISEASE. This is one of the most common of equine 

 ailments, and, at the same time, the least amenable to treatment. It 

 consists in an inflamed and ulcerated condition of a small bone in the 

 foot termed the navicular bone (see fig. 92, page 399). Light horses 

 engaged in fast work as hunters, hacks, and harness horses are most 

 frequently its victims. It is undoubtedly hereditary (page 410), and so 

 much so in some instances as to make its appearance in quite young 

 horses even as early as three years of age. The great majority of cases, 

 however, are the direct consequences of long continued work and wear 

 on the hard roads of our commercial towns. Horses with high action 

 are very prone to it, especially if the feet are strong and blocky, or low, 

 flat and weak, or where the pasterns are upright and wanting in length 

 and elasticity. 



Symptoms. Navicular disease is generally gradual in its onset, and 

 slowly but surely progressive in its course. In the early period of the 

 attack the symptoms are never very diagnostic. A slight alteration in 

 the animal's gait is first noticed after a hard day's work, when the fore 

 limbs appear to lack their usual liberty of action, and there is a slight 

 tendency to trip and stumble. The movements soon become stiff, and 

 later on lameness shows itself in both fore limbs, not equally but 



