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Contagious Poot-rot in Sheep. 
Disease beginning in the Hoof. 
A remarkable instance of the first form of foot disease was 
met with some years ago in Somerset and Dorset, and the follow- 
ing illustrations will show the changes which had occurred. 
Three distinct conditions of the horny covering of the foot 
were recognised. The disease commences in the hoof itself, as 
has been stated, the alteration of the internal structures taking 
place subsequently. One condition extremely marked is the 
decay of the horn at the toe, and the passage of particles of sand 
and dirt through the openings in the shrivelled hoof at the toe 
into the interior of the foot. See Fig. 1 (1). 
Then a second condition is the overlapping of the lower 
edge of the wall of the hoof, illustrated in Fig. 1 (2), leading to 
the retention of grit and sand, which, owing to the pressure on 
/ 
Fig. 1. — Foot of sheep showing disease of horn. 
Fig. 2.— Section through the foot 
allowing a crack extending through 
the wall. 
the base of the foot in the ordinary course of movement, is 
driven through the spaces between the horn fibres into the 
interior of the horny cavity. 
A third condition is the existence of a minute fissure in 
some part of the hoof, commonly at the outer surface of one of 
the digits, indicated on the white hoofs of the Dorset and 
Somerset sheep by a dark line, sometimes not more than the 
sixteenth, and rarely more than the eighth, of an inch in length, as 
shown in Fig. 1 (3). The consequence of these changes of structure 
is exactly the same in each case : the passage of gritty material 
into the interior of the horny box, either through the decayed 
horn at the toe, or through the sole under the overlapping wall 
of the foot, or through the small fissure in the wall of the hoof. 
