Thehorse.com - Full Article
by: Michael Ball, DVM
May 01 2003, Article # 4335
Thrush is very common, and it typically is a mild disease that can be easily treated. More importantly, it can be prevented with adequate foot management and good stable husbandry. However, if you choose to ignore these preventive measures, or you come into possession of a horse with thrush, it needs to be addressed immediately and aggressively as complications and chronic lameness issues can result. Thrush can be very insidious in the early stages, and it can become severe enough to cause permanent lameness.
First, let's discuss some descriptive anatomy of the foot to better understand the problem. When looking at the foot from the bottom, the hoof wall circles from the lateral (outside) heel around the point of the toe (the dorsal surface) and on to the medial (inside) heel. The frog is the brownish/ black rubbery-textured triangle with the flat base at the heel and the point two-thirds of the distance to the toe (see page 92).
The remainder of the whitish structure on the bottom of the foot is the sole. The frog has a central invagination or groove called the central sulcus, and the deep grooves at its junctions with the sole are the lateral and medial sulci (sometimes called the paracuneal grooves)...
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