Horses commonly develop lower leg wounds and some of these wounds are difficult to heal as proud flesh is a major inhibitor of healing in equine wounds.  Proud flesh is actually correctly called exuberant or excessive granulation tissue.  Granulation tissue is needed to fill in the defect of the wound if it is not sutured.  However, in horses, the granulation tissue does not stop growing once the wound defect is filled but keeps growing out of the wound and prevents healing. 

The question today is about understanding when to bandage lower leg wounds in horses or leave them open to air out.  And the answer is it depends on a lot of factors, one of which is your geographic location.  Although not reported in the literature, it seems we have a lot more problems with proud flesh in Texas and other warm climates than in colder climates.  I don’t know if this is due to temperature, flying insect irritation or humidity but many wounds are left open in colder climates while most of ours in Texas require a bandage, at least initially, with medication to retard growth of proud flesh.  Some scientific studies indicate that bandaging decreases oxygen supply to the wound and increases proud flesh, and this may be correct unless you use medication to control it.  However, in my experience, it is difficult to control proud flesh in Texas if you leave the wound open.  If proud flesh does develop, the best treatment is to have your vet remove it surgically as medications to remove proud flesh damage surrounding tissue and further delay healing.  I think wrapping all lower leg wounds in horses is initially a good idea and then allow your vet to examine the wound, and further bandaging recommendations depends on the area of the wound and its healing status.