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We shall first speak of the causes to which navicular disease is to be 

 ..attributed ; then of its symptoms and methods of detection, in this connection 

 dealing with contracted foot ; and, lastly, we shall review some of the various 

 methods of treatment, unfortunately in many instances so futile. 



Hereditaiy influence, that potent predisposing factor in the causation of 

 so many diseases, is often clearly traceable in navicular disease. The 

 practical conclusion to be deduced from this fact is, that animals afflicted 

 with this malady should not be used for breeding purposes. It has been 

 said, and we believe with good reason, that feet with high heels are more 

 liable to navicular disease than open flat ones. When the soles are flat, 

 there is necessarily more constant pressure on the frog, which, together with 

 the structure it supports, is thus maintained in a more healthy state. It 

 must be borne in mind that heredity is probably of influence not so much in 

 predisposing animals to inflammation of the navicular bone, as in transmitting 

 to the offspring that peculiar shape of foot which is especially liable to lead 

 to such changes in this important structure. In any case the knowledge that 

 heredity plays a great part in the production of this disease is of value, as 

 indicating that affected animals should not be used for stud purposes. 



When we consider that the hind feet are very rarely affected with 

 navicular disease, but that the fore feet are very commonly so diseased, one 

 naturally expects to find some cause which, though very rarely resulting in 

 changes of this kind, is very potent in leading to disastrous lesions in the fore 

 feet. What is the cause ? It has often been noticed that this affection is far 

 more commonly met with in horses used for quick work on hard roads, than 

 among other animals. We naturally infer from these facts that navicular 

 disease is largely dependent upon concussion or undue jarring, which 

 necessarily affects the fore more than the hind feet, and is more violent and 

 sustained in roadsters and hacks. 



The disease, it may be stated, often begins in the membrane lining the 

 navicular joint, or in the cartilage lining the surface of the bone, which is the 

 spot where we should expect that the effects of constant and violent 

 concussion would be especially liable to result in inflammatory changes. 



Among hunters and racers, navicular disease is not nearly so common ; 

 for their work on softer ground does not cause this violent jarring. It is to 

 the quick, long journeys made on the hard roads that this inflammation 

 leading to such disastrous consequences is mainly due. Regarding these 

 points Mr. Stewart long since wrote, "long journeys, performed quickly, will 

 make almost any horse 'groggy.' Bad shoeing and want of proper care alsp 

 help, but alone they never produce this affection. The animal must journey 

 far and fast ; but, if his feet be neglected, or the shoeing be bad, a slower 

 pace and a shorter distance will produce the mischief" 



As we might expect, navicular disease is almost unknown among cart- 

 horses ; but they are more subject to laminitis than finer bred animals. In 

 addition to the major causes of navicular disease, there are some minor ones 

 we may shortly mention. Rheumatism is believed by some to be a 

 cause of navicular disease, but we do not think this is ever the exciting factor. 



