DISEASES OF THE FOOT. 507 



1023. Symptoms. 



The lameness may appear suddenly. No cause can be found for it. 

 It may probably disappear, and after a time reappear either in the same 

 or in the other foot, and these appearances and disappearances may occur 

 for some time. Such is usually the case when the disease is due to rheu- 

 matic affection. In time the symptoms become more marked. 



Or the first sign may be pointing of the foot in the stable, followed 

 after a time by shortness in the step and perhaps by lameness. The 

 foot and the horse may be examined, and nothing wrong can be found. 

 Probably the next day the animal may be sound. But in the course of a 

 few days the symptoms become more marked. 



Pointing in the stable is common with many horses as an act of rest 

 or as a mere matter of habit. When, however, pointing arises from 

 habit, or as an act of rest, the animal stands with one fore-foot arid then 

 with the other, in a semi-flexed position, in a careless lounging way ; but 

 he points two limbs simultaneously, namely, one fore and the hind leg of 

 the opposite side of his body. In navicular disease, however, a fore-foot 

 or feet only are pointed. There is no corresponding resting of the hind 

 limb. 



The above signs may lead us to suspect navicular disease as the cause 

 of lameness. But the strongest indication of the disease lies in the 

 absence of any cause, such as external injury or heat sufficient otherwise 

 to account for the lameness. The fact of intermittent lameness in the 

 earlier stage, and of persistent lameness in the later stage, without any 

 external symptoms sufficient to account for it, is the strongest indication 

 that the disease lies in the navicular bone. 



The symptoms of lameness are evidently those of foot lameness (see 

 Chapter 42, Par. 654). If laminitis be present, there will be heat and 

 tenderness, and the animal will go more or less on its heels. If a corn 

 be the cause, its presence is easily detected. In fact, in nearly every 

 other form of disease there are external signs, which will at once point 

 to the cause of disease. But in navicular disease, if we except occasional 

 heat and tenderness in the hollow of the heel, or redness of the frog and 

 sole immediately below the navicular bursa, there is no external sign. 

 Even the redness of the frog and sole, now and then met with, is not 

 always to be depended on as a sign of navicular disease, as it may arise 

 from external injury, such as .treading on a stone, and may be superficial 

 only. 



In navicular disease, pressure on the hollow of the heel will very often 

 give pain ; and the pain so evinced is no doubt symptomatic of the exist- 

 ence of the disease. But it is necessary to remark, that any great pres- 

 sure on the heel and violent flexing of the pastern will often cause even a 

 sound horse to show signs of pain. Therefore this symptom cannot be 

 absolutely relied on. 



In the more advanced stage, the horse will often come out of his stable 

 lame after an interval of rest. He may scarcely be able to put his foot 

 to the ground, but after he has been exercised a short time the great 



