The
hoof wall grows from the coronary band,
down the front of the pedal bone, the laminae allowing it
to remain attached to the bone, and yet gradually slide down
towards the ground. The rate of growth in unshod horses will
adapt so that it equals the rate at which the horn is worn
away at the ground surface. With modern, hard road surfaces,
the horn wears to fast, and the growth cannot keep up with
the wear rate, so shoes may need to be applied to curtail
this wear.
Shown
right is a Solar view of
the foot -
Note how the wall at the
heels is turned forwards to form
the bars. The bars are largely
responsible for giving support to
the heels, and stopping them collapsing forward under
the foot when weight-bearing.
The
hoof is designed to be able to absorb concussion of
the horse with every step it takes. This is carried
out by an interaction between pressure on the pedal
bone resulting in blood flow (in one direction) up
the veins. This is known as the 'foot pump' which
acts as a shock absorber reducing concussion up the
limb. Some of the concussion of movement is also absorbed
by the hoof wall which bends and the heel which speads.
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