Final answer:
Thrush is a bacterial infection in horses that commonly occurs in the frog, the V-shaped soft tissue in the hoof. It has a distinctive odor and is characterized by black, necrotic material.
Step-by-step explanation:
In horses, Thrush is a common bacterial infection that occurs in the hoof, particularly in the frog, which is the V-shaped soft tissue located between the sole, bars, and heel of a horse's hoof. It is easily recognizable by its foul odor and the black, necrotic material often seen in the area of the frog. Thrush is commonly caused by damp, dirty living conditions, and poor hoof hygiene, which allow anaerobic bacteria and sometimes fungi to thrive.