206 HORSESHOEING. 



from the hollow section of wall, we cleanse the cavity and 

 fill it with oakum and tar, cinide turpentine, or w^ax. Where 

 the separation is very extensive we use a har-shoe. 



The time required for complete cure of hollow and loose 

 walls will depend upon the height of the separation (see growth 

 of the hoof, page 82). 



5. Thkush of the Frog. 



Wlien the horny frog is ragged and fissured, and an ill- 

 smelling, dark-colored liquid collects in the lacunfe of the frog, 

 it is affected with thrush. When thrush exists uninterruptedly 

 for several months the perioplic band is irritated and forms 



rings of periople which 

 ^^" ^' assume an in-egular 



course and cross the 

 rings of the middle 

 layer of the wall (Fig. 

 224). 



The causes: un- 

 cleanliness, too little 

 exercise in fresh air, 

 excessive paring of the 

 frog, and the use of 

 shoes with calks by 

 which the frog is 



Hoof with irregular superficial rings resulting from thrush pemianentlv rCmOVed 

 of the frog. <- . i " i 



from the ground. 



The consequences are, besides contraction of the hoof, sore- 

 ness in travelling, a shortening of the step, and, occasionally, 

 well-marked lameness. 



Treatment. — Removal of all greasy horn from the frog, and 

 of the prominent overgrown angles of the buttresses (see page 

 100), thorough washing of the frog once or twice daily with a 

 5 per cent, creolin or carbolic solution, abundant exercise, and 

 shoes without calks, 



