196 



HORSESHOEING. 



Fig. 216. 



Occurrence.-^On. the inner side of front hoofs, especially of 

 horses that stand base-mde ; on hind hoofs, usually at the toe. 

 Classification. — According to location we distinguish toe- 

 cracks, side-cracks, quarter-cracks, and bar-cracks. Those 

 cracks which affect only tlie upper border of the hoof are called 

 coronary cracJcs; those which are limited to the lower border of 

 the hoof are sometimes designated low cracTcs (plantar cracks) ; 

 while those which are continuous from one border to the other 

 are called complete cra-cJcs. If the crack passes through the 

 entire thickness of the wall to the sensitive tissues imdemeath, 

 it is called a deep or penetrating 

 crach, in contradistinction to the 

 superficial erack (Fig. 216). 



Causes. — There are many. Be- 

 sides wounds of the coronet, every- 

 thing that impairs the elasticity of 

 the horn, weakens the hoof, and 

 causes an overloading of one-half of 

 the hoof. Furthenuore, great dry- 

 ness and excessive work on hard 

 streets. 

 Prognosis. — This will depend upon the age, kind, and loca- 

 tion of the crack. A low crach is without significance unless 

 it is the remnant of an old coronary crack which has gro^\Ti 

 do\\Ti. Coronary cracks, on the contrary, are more serious be- 

 cause of the lameness which often accompanies them, and 

 especially on account of the long duration of the healing process. 

 The borders of the crack never grow together, and healing 

 can only take place through healthy, unbroken horn growing 

 down from the coronary band. 



{a) Treatment of Coronary and Bar-Cracks. — If practic- 

 able, allow the affected horse to go barefoot; otherwise, the 

 use of the bar-shoe for all cracks is advised, because it will 

 continuously protect the diseased section of wall from pressure 

 by the shoe. If there are present still other diseases of the 



Hoof exhibiting a coronary crack, a 

 plantar or low crack, and a complete 

 deep crack, the latter with a nail ready 

 to be clinched. 



