Effect of locally injected medications on healing of pad wounds in dogs.

OBJECTIVE

To ascertain the effects of locally injected immunostimulant and tripeptide-copper complex (TCC) on improving healing of pad wounds.

DESIGN

Wounds in pads of large dogs were injected with either medication or physiologic saline solution (controls). Healing was evaluated.

ANIMALS

12 mature English Pointers.

PROCEDURE

Full-thickness 6 x 8-mm wounds in metatarsal and third and fourth digital pads were injected with immunostimulant or TCC at 0, 3, and 6 days after wounding. Wounds on control dogs were injected with physiologic saline solution. Using planimetric measurements at 0, 3, 6, 14, and 21 days, rates of healing were evaluated. Biopsy of the digital pad wounds at 3, 6, and 14 days was used to evaluate collagen content by hydroxyproline analysis. Biopsy specimens were also evaluated for type-I and type-III collagen, using Sirius red differential staining.

RESULTS

Effect on healing rate and hydroxyproline content was best during the first week for immunostimulant. Immunostimulant- and TCC-injected wounds had more type-I collagen than did controls at 6 days; TCC-injected wounds had the most type-I collagen. At 14 days, the amount of type-I collagen in TCC-injected wounds was significantly greater than that in other wounds.

CONCLUSIONS

Tested medications had positive effects on healing of pad wounds.

CLINICAL RELEVANCE

Intralesional injection of medications helps ensure their presence for enhancement of wound healing. The benefit could be lost with topical use in a bandage if the bandage is lost or becomes wet.