Recent research out of the University of Sydney suggests that Manuka honey reduces wound size and healing time of horses’ leg wounds. It’s the first clinical trial of Manuka honey conducted in horses. Sweet!
[Top photo by Wikimedia Commons]
“Wounds in horses, particularly leg wounds, have long healing periods. But we found applying a Manuka honey gel throughout healing led to 27 percent faster healing times,” says lead researcher Dr. Andrea Bischofberger. Dr. Bischolfberger is a Swiss veterinarian currently with the Research and Clinical Training Unit (REaCT) at the University Veterinary Teaching Hospital in Camden, a part of the University of Sydney.
“Wounds in horses which received no treatment took an average of 64 days to heal, while those treated with Manuka honey gel took 47 days to heal,” she says.
The findings are the result of three clinical trials conducted at the University.
Study 1: Is Honey Effective?
“The first study was to prove efficacy, so one standardized wound was created on each front cannon bone. Because the honey was liquid, we bandaged each leg and applied the honey daily for 12 days,” says Dr. Andrew Dart, REaCT Director. Professor Dart is a surgical specialist and expert on the complications associated with lower leg wound healing in horses. He is supervising Dr Bischofberger’s research.
A previous study conducted by Dr. Dart found that semi-occlusive dressings (dressings that allow gas and water to pass through) on horse limbs are predisposed to excess granulation tissue, or proud flesh. Removing the bandages at 12 days reversed the effect.
“Wounds that are bandaged for 12 days retract more and therefore are larger than unbandaged wounds. So, bandaging for 12 days aids in producing a more natural wound-healing model, as compared to just creating standard surgical wounds using a scalpel blade under aseptic conditions. As a result, the model used to test the honey was a better than earlier models,” he says.
Wound size in the pilot study on honey was measured from standardized photographs using digital imaging. “What we found was that honey treated wounds retracted less and were smaller than untreated wounds out to day 42, but overall healing was not affected,” says Dr. Dart.
Study 2: What about Diluted Honey?
In the second study, the researchers developed a Manuka honey gel of 66% honey and 34% water-based gel. “This was based on information from the ancient Egyptian literature where they found diluting honey had no effect on efficacy,” explains Dr. Dart.
Multiple wounds were created on each leg. The wounds were bandaged for 12 days and contaminated for 24 hours to try and recreate a more naturally occurring wound. “We treated wounds with honey alone for 12 days, honey gel for 12 days, honey gel throughout healing, gel alone and control wounds,” he says.
Honey and honey gel were found to be equally as effective. “The wounds treated with honey and honey gel retracted less and were smaller than control and gel treated wounds out to day 35,” says Dr. Dart.
While wounds treated with honey gel throughout healing healed faster than all other wounds. “The main effect of honey was in the first 21 days and primarily in the first seven,” he says.
Dr. Dart added that contaminated wounds retracted more and healed faster than uncontaminated wounds suggesting some contamination may be beneficial to lower leg wound healing in horses.
Study 3: Mechanism of Action
In a third study, Dr Bischofberger and colleagues investigated how Manuka honey actually worked to speed up wound healing. Currently, the mechanism of action is unknown.
“What we do know is treating wounds with Manuka honey leads to healthier tissue regrowth,” says Dr. Bischofberger. “Wounds treated with Manuka also showed improved new blood vessel and skin surface growth compared to control wounds.”
“There is evidence Manuka honey has antibacterial effects against antibiotic-resistant organisms, a non-peroxide and peroxide activity and a direct effect on the inflammatory process. We are currently investigating this,” adds Dr. Dart.
“Our research is leaning towards the fact that the antibacterial effects are not as important as the effect of creating a more mature granulation bed early in the disease process. This may be through the effects of Manuka honey on the immune system.”
Will Any Honey Do?
Manuka honey with a Unique Manuka Factor (UMF) of 20 was used in the studies. However, Dr. Dart says UMF 10 or greater has increasingly beneficial effects on antibiotic-resistant organisms and will likely improve wound healing.
“Assuming this is one of the mechanisms of action in the horse then one would recommend UMF 10 or greater. Saying that, all honeys have some antibacterial effect,” he says.
Dr. Dart uses Manuka honey widely in his clinical practise for open wounds that cannot be stitched. “Our research would suggest application daily for at least 7 days, ideally for 21 days, is desirable with some effect if applied throughout healing.”
There are no known adverse effects associated with the topical application or ingestion of honey in horses.
“It is safe to use,” says Dr. Dart. “I say use it sparingly—a light smear over the wound—because it is obviously sticky and will attract dirt and contaminants if used too heavy handedly. It would be better to apply it twice daily sparingly rather than a big glob once daily.”
Contrary to convention, you will not attract more flies with honey treatments. “Flies are not any more of a problem than they are normally. Obviously, it does not contain fly repellent. If flies are a problem, then there is no reason not to apply the honey and lightly apply a fly repellant around the wound,” says Dr. Dart.
“If anything the biggest problem is that some horses may get a taste for it and want to lick it off. In that case, if it is a real issue, then applying some sort of light bandage (even cut up baby nappies locally over the wound for an hour or so to let the honey soak in and have an effect or apply twice daily as an alternative. Either scenario is uncommon in our experience.”
Honey, now you know.
Carley Sparks covers show jumping and related ridiculousness at getmyfix.org.