Kinetics of healing of grafted and nongrafted wounds on the distal portion of the forelimbs of horses.

Full-thickness, circular, cutaneous wounds (5 cm in diameter) were created on the distal portion of the forelimbs of 6 horses. One wound on each horse was treated with 6 full-thickness punch grafts that were obtained from the horse's neck with a 6-mm skin biopsy punch and inserted in the graft sites on day 14 after wounding. The wound on the contralateral limb was not grafted. A combination of ticarcillin disodium and clavulanate potassium was applied to the wounds when bandages were changed to control bacterial infection. Areas of each wound were measured on days 1, 7, 9, 11, 13 through 15, 17 through 22, 24, 26, 29, and 32 after wounding. Three distinguishable phases of healing were observed (expansion, contraction, and epithelialization), and the time course of each phase was evaluated, using formulas of first-order processes. Rate constants of each phase were not significantly (P less than 0.05) affected by punch grafts.