Cracked Heels in Horses. 519 



The causes are extremely varied, consisting in the application 

 of irritants of many kinds, to the susceptible skin in a system. 

 too often already predisposed to skin disease. 



Standing on reeking dungheaps, or on heating manure in 

 filthy stalls subjects the heels, and especially the hind ones, to 

 ammonia and other irritating fumes, and when taken out to the 

 cold air, chill water and mud, the sensitive parts suffer. Again 

 in the farm yard and even in neglected stalls the hind feet are 

 immersed in pools of liquid manure, the ferments and toxic mat- 

 ters of which dry on the skin, attack the surface and determine 

 septic congestions and inflammations. On country roads where 

 there is no pretense'of pavements, or macadam, themiud in spring ■ 

 and fall is a source of great irritation on certain soils which con- 

 tain small flat stones, pebbles or sand, or in which lime or de- 

 composing manure is a prominent feature. Standing in snow or 

 slush, especially if chilled by salting, produces partial or com- 

 plete congelation with the result of chillblains or even more 

 active and destructive inflammation or sloughing. The habit of 

 washing the heels and allowing them to dry spontaneously in the 

 stall is only less injurious by the chill induced. This is still 

 further aggravated by the use of caustic soaps on the already 

 tender skin. The lighter breeds of horses, devoid of long hair 

 on the pasterns, though less subject to the greasy secretion, are 

 even more exposed to chills and direct injuries, and suffer readily 

 and often persistently from erythema and cracks. In many cases 

 trouble comes from the ends of stubble and other vegetables 

 acting on the skin. A common fault is the close clipping and 

 even singeing of the hair in the hollow of the heel. The stiff, 

 bristly ends of the hairs on one fold of the pastern continually 

 prick the skin of the adjacent fold when the animal is in motion 

 and not only is this irritating to the healthy skin, but it becomes 

 incomparably more so when that is congested and tender. 

 Even in summer the deep dust on unpaved roads, mixing 

 with the normal secretions of the heel, rolls into semi-solid masses 

 between the folds and proves the more irritating, the greater the 

 admixture of sand or solid bodies. A common cause is the stock- 

 ing of the limbs, with the attendant congestion, distension and 

 debility of the skin. This may be due in its turn to a great 

 variety of proximate or remote causes, lymphangitis, sprains. 



