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After division of the nerves, the part below the seat of section loses sensory 
power, and, no pain being felt, the animal often ceases to manifest lameness, 
It is scarcely ever advisable to perform neurotomy on a young horse. 
Some time ago, we performed the operation on a four-year-old colt, on which 
all other methods had been tried. The animal has since been perfectly 
sound, having made a good recovery. Our readers must bear in mind that 
the treatment of navicular disease is at best mainly unsatisfactory. It is 
always well to dispose of animals so affected, when an opportunity offers 
itself, 
SANDCRACK, 
By a sandcrack we understand a longitudinal fissure of greater or less 
extent in the horny fibres of any part of the wall of the hoof, commencing 
close to the coronet, and mostly found at the inner quarters of the fore feet and 
at the toes of the hind feet. More rarely these fissures are met with'in the 
outer quarters. At first the fissure is small, but it gradually extends 
downwards and inwards. Wherever situated, sandcrack constitutes 
unsoundness. 
In the healthy horn, the fibres are held together by an agglutinating 
cellular substance, and therefore they do not become separated.¢@, When, 
however, the secreting membrane is injured by concussion or other cause, 
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