Types and Market Classes of Live Stock 411 



The sole horn is circular in shape except that it is notched at the 

 rear where it receives the bars and horny frog. It is naturally concave 

 below and is bounded at its edge by the wall and bars. It is very 

 brittle, non-elastic, and easily penetrated. The sole horn is produced 

 by the fleshy sole, which is that portion of the pododerm covering the 

 entire under surface of the foot excepting the fleshy frog and bars. 



The horny frog does not come in contact with the sole horn except 

 at its apex. It is tough, elastic, and rather soft horn. The upper 

 part of the horny frog has an elevation or ridge and on the bottom 

 there is a corresponding notch or groove. The horny frog grows from 

 the fleshy frog, which is that part of the pododerm just above the horny 

 frog. 



The preceding discussion of the parts of the hoof and pododerm 

 may be summarized as follows: 



IPerioplic layer, produced by perioplic ring. 

 Coronary layer, produced by coronary cushion. 

 Laminous layer, produced by fleshy laminae. 



2. Sole, produced by fleshy sole. 



3. Frog, produced by fleshy frog. 



All parts of the hoof grow downward and forward with equal 

 rapidity, the rate of growth being largely dependent upon the amount 

 of blood supplied to the pododerm. Abundant and regular exercise, 

 good grooming, moistness and suppleness of the hoof, going barefoot, 

 plenty of good food, and at proper intervals removing the over-growth 

 of the hoof and regulating the bearing surface — all these, by increasing 

 the volume and improving the quality of blood flowing into the podo- 

 derm, favor the rapid growth of horn of good quality. Lack of exer- 

 cise, dryness of the horn, and excessive length of the hoof hinder growth. 

 The average rate of growth of the hoof is about one-third of an inch a 

 month. Irregular growth often occurs. This is almost always due to 

 an improper distribution of the body weight over the hoof, — that is, 

 an unbalanced foot. An authority on this subject says: ^ "If breeders 

 were more generally cognizant of the power of overgrown and unbal- 

 anced hoofs to divert the lower bones of young legs from their proper 

 direction, we might hope to see fewer knock-kneed, splay-footed, 

 pigeon-toed, cow-hocked, interfering, and paddling horses." 



Characteristics of a healthy foot.— ^A healthy foot is equally warm 

 at all parts, and is not tender under pressure with the hands. The 

 coronet ^ is soft and elastic at all points and does not project beyond 

 the surface of the wall. The wall is straight from coronet to ground. 



^Dr. John W. Adams, University of Pennsylvania: Shoeing, U. S. Dept. 

 Ag^r., Bur. Anim. Indus., Special Rpt., Diseases of the Horse, Revised, p. 558. 



2 The coronet or "hoof head" is the lower end of the pastern immediately above 

 the hoof. 



