408 



the fissure are entirely removed with the knife. Tlie horn removed 

 is in the shape of the letter V with the base at the coronet. Care 

 must be taken not to injure the coronary baud and the laminse. The 

 wound is to be treated with mild stimulant dressings, such as a weak 

 solution of carbolic acid, tincture of aloes, etc., oakum balls, and a 

 roller bandage. After a few daj'S the wound will become covered 

 with a new, white horn, and the oakum and bandages only will be 

 needed. As the new quarter grows out the lameness disappears, and 

 the patient may be shod with a bar shoe and returned to Avork. 



In all cases of sand crack the growth of horn should be stimulated 

 by cauterizing tlie coronary band, or by the use of blisters. In sim- 

 ple quarter crack recovery will often take place if the coronet is blis- 

 tered, the foot shod with a "tip," and the patient turned to pasture. 



The shoe, in toe crack, should have a clip on each side of the fis- 

 sure and should be thicker at the toe than at the heels. The foot 

 should be lowered at the heels by f>aring, and spared at the toe, 

 except directly under the fissure, where it is to be pared away until it 

 sets free from the shoe. 



When any of the complications referred to above arise, special 

 measures must of course be resorted to. For the x^rojier treatment of 

 gangrene of the lateral cartilage and extensor tendon and caries of the 

 coffin bone, reference maj^ be had to the articles on quittors. If 

 the horny tumor known as keraphyllocele should develop it is to be 

 removed by the use of the knife. Since this tumor develops on the 

 inside of the horny box and may involve other important organs of 

 the foot in disease, its removal should only be undertaken by a skillful 

 surgeon. 



NAVICULAR DISEASE. 



Navicular disease, often called "navicular arthritis" by the English, 

 is an inflammation of the sesamoid sheath, induced by repeated bruis- 

 ing or laceration, and comi)licated in many cases by inflammation and 

 caries of the navicular bone. In some instances the disease undoubt- 

 edly begins in the bone, and the sesamoid sheath becomes involved 

 subsequently by an extension of the inflammatory process. (Plate 

 XXXII, Fig. 5.) 



The thoroughbred horse is more commonly affected with the disease 

 than any other, yet no class or breed of horses is entirely exempt. The 

 mule, however, seems rarely, if ever, to suffer from it. For reasons 

 which will appear when considering the causes of the disease the hind 

 feet are not liable to be affected. As a general rule but one fore foot 

 suffers from the disease, but if both should be attacked the trouble 

 has become chronic in the first before the second shows signs of the 

 disease. 



Causes. — To comprehend fully how navicular disease may be caused 

 b}' conditions and usages common to nearly all animals it is necessary 



