Q:My horse had a cut on his lower cannon bone and my vet gave me instructions on how to wrap it to prevent proud flesh. What is proud flesh, and can it really become a problem, or is he being overly cautious?

A:Exuberant granulation tissue, or proud flesh as it is more commonly known, is part of the normal wound healing response in the horse. Granulation tissue is the pebbly or granular appearing tissue which develops in healing wounds anywhere on the horse’s body. Granulation tissue is composed of small blood vessels and fibroblasts, but has no nerve supply. Granulation tissue forms primarily in wounds left open to heal, rather than those wounds that are primarily closed (sutured). This healing tissue is beneficial within open wounds for several reasons:1) Granulation tissue helps the open wound resist infection; 2) As it fills the healing wound, it provides a surface for the epithelial (skin) cells on the periphery of the wound to "crawl" over and help cover the wound; 3) Granulation tissue helps aid the wound in contracting or becoming smaller.

Granulation tissue is a very important and necessary part of wound healing in the horse. However, there can be problems when the horse develops too much granulation tissue.

Research has found that horses have the ability to produce granulation tissue in wounds quite rapidly when compared to other animals. When granulation tissue grows out and protrudes from the wound, then the granulation tissue is known as proud flesh. Proud flesh is not conducive to wound healing as it prevents the wound from epithelializing (the process of the skin cells covering the wound)