DISEASES OF THE FOOT. 503 



the lainime must be cut away with, the knife ; and if the disease shows 

 signs of extending, such further portions as may be necessary must be 

 cut away. The hollow so made in the crust should be filled up with 

 artificial horn made of gum arable and gutta percha poured in liquid. It 

 will soon become hard and may be secured by a nail driven through and 

 clenched. A ledge may be made in the upper part of the sound crust, 

 which will assist in retaining it in its place. A bar shoe should l)e 

 applied with the view of relieving the anterior portion of the foot. The 

 shoe must not have a clip at the toe. Lastly, with a view of promoting a 

 healthier action of the parts, the coronet must be frequently blistered. 

 A long rest without shoes will in general cure Seedy Toe without any 

 treatment. 



1015. Thrush. 



The structures and functions of the frog and the treatment needed to 

 maintain it in health were described in Chapter 62, par. 952. 



Thi'ush is, to the discredit of our stable management, a common dis- 

 ease. It shows itself under the form of an acrid, strong-smelling, un- 

 healthy secretion issuing from the sensitive frog through the cleft of the 

 external or insensitive frog. The causes of the altered secretion of the 

 internal structure may be summed up under two heads, viz. — 1st, wet and 

 dirt, or, in other words, neglect ; and 2nd, want of use. 



To maintain the frog in health, it should be washed scrupulously clean 

 every day with a hard water-brush, and the feet picked out at each 

 stable hour. The mere fact of dung being allowed to remain in the feet 

 is often sufficient in a few days to induce thrush. Again, the ammonia 

 and other gases generated by dirty or decaying litter act most injuriously 

 on the structures of the frog. Hence it is essential that the floor of the 

 stable should be well paved, thoroughly drained and kept clean. The 

 litter should also be dried and aired every day. Continued wet, such as 

 may occur to horses in camp, has likewise a mischievous effect in soften- 

 ing the external structure, which then ceases to afford due protection to 

 the sensitive parts within. But it is from the effect of dirt, combined 

 with wet, that the frog suffers most rapidly. 



Disease in the frog is also readily induced by paring, contraction, high- 

 heeled shoes, or any other causes which bring it into disuse. 



Work, wear, and pressure are natural to the frog and essential to its 

 health and development. If, however, by being constantly pared away 

 at each shoeing, or by any of the above-mentioned causes, the frog is 

 deprived of pressure and wear, it soon becomes unhealthy and diseased. 

 In feet which have been for some time affected with navicular disease, a 

 similar effect is produced on the frog ; because the horse, on account of 

 the disease, the seat of which is immediately above the frog, saves as 

 much as possible that portion of his feet and treads on his toes. It is, 

 however, a singular fact that this effect on the frog is often not found iu 

 the earlier stage of navicular disease. (See par. 1021.) Again, in con- 

 tracted feet the sole is generally so much recessed that the frog hardly 

 ever comes to the ground, and hence from want of use it becomes diseased. 



