Properly Dealing with Equine Wounds and Scratches
Treating a wound on a horse is different than treating a wound on you or me. Horse wound care requires a little attention than the typical equine injury. The most important thing to do when treating wounds is to keep them clean and dry; this is where horse first aid kits come in so handy. When a wound heals after being stitched, this is known as “first intention” healing, and the resulting scar is very small. For this to occur, the wound must be clean and fresh when sutured.
Unstitched wounds, or stitched wounds that break down, heal by what is known as “second intention” healing. In this process, the deepest and outermost parts of the wound heal first. The repair begins at the edges, and the initial blood clot, which later forms the scab, is replaced by new tissue, or granulation tissue, which begins growing inward from the borders of the wound. Later, new skin grows in from the edges to cover the granulation tissue.
The decision to stitch a wound depends on how fresh it is, the depth, and its position on the horse’s body; wounds on the head and body heal well, while those on the limbs tend to be less successful. If the wound is fresh, it is best not to touch it before a vet arrives, other than trying to prevent it from being contaminated. The wound should not be washed with a disinfectant because they may damage the tissues and reduce healing capacity.
Uncontaminated, warm water should be used to clean a wound; the wound can be dressed and bandaged with horse first aid supplies until the vet arrives. If the wound is not fresh (12 to 24 hours old), it will already be contaminated with bacteria from the skin; there is little point in stitching it now since the stitching will only seal the infection inside. Most infected wounds heal very well by “second intention” healing.
Contaminated wounds can be cleaned with cotton and a solution of mild medical disinfectant. A suitable antibiotic ointment should be applied to the area, under a quilt and bandage. The ointment not only reduces infection and helps healing, but stops a lint or quilt dressing from sticking to the wound; squares of paraffin gauze can also be used as dressings under lint bandages, achieving a similar non-stick outcome.
Deeper wounds on certain parts of the limbs are likely to involve damage to important inner structures. The deep flexor tendon is sometimes severed by wire wounds at the back of the pastern; the superficial flexor tendons can be cut by over-reach wounds or by being “struck into” from behind above the fetlock. These are serious injuries; it may even be necessary to stitch together tendons that have been completely severed. A veterinarian should be contacted immediately if deeper structures appear to be damaged. Keep in mind that tetanus can develop following a wound. If your horse is not vaccinated against the disease, it must have an injection of tetanus antitoxin each time it suffers a wound to give it temporary protection.
Wound healing in horses differs from that of other species in that the granulation tissue tends to form in amounts far larger than necessary. This is a very important aspect in horse health. Various factors such as water, irritant powders and ointments also encourage the formation of extra granulation tissue. The tissue grows beyond the normal level of the skin surface forming a bright pink lump that is commonly called “proud flesh” by horsemen. Although wounds in other species normally heal better when exposed to air and left un-bandaged, those in horses tend to form proud flesh unless pressure is applied to them. Therefore, it is necessary to keep a pressure bandage on limb wounds on horses while they are healing. This may take at least two to three weeks or even longer for large wounds.
Wounds should not be washed during healing; wetting can by itself stimulate proud flesh formation. The area will do just fine simply wiping away any discharges with a dry or slightly moistened piece of lint or quilt when changing the dressings every day. If the bandage is removed too soon, or if a bandage has not been used at all, it will be necessary to remove the resulting lump of proud flesh because the new skin will be unable to grow out over the surface to cover it; it must be brought back down to skin level. This is usually done by chemical cauterization using an irritant solution containing copper sulfate. Proud flesh has no nerve supply, and a few day’s application of the solution is normally enough to do the trick. It may be necessary to remove large pieces of proud flesh by a form of surgery, but this is a rare occurrence.
Puncture wounds should never be stitched; they should be cleaned, dressed, and allowed to drain so they can heal from inside first. If foreign material is present in the wound, it will go on discharging for many weeks, unless the object is removed. If there is a possibility that something has been lodged inside the wound upon injury, a vet should be contacted to remove it. Injuries can be very serious if a joint or tendon sheath is punctured. In a flesh wound, viscous straw-colored tendon-sheath fluid or joint lubrication fluid (synovial fluid) can be seen. If there is any suspicion that either a joint or tendon sheath is involved in a wound, call the vet immediately.
Extensive treatment with antibiotics, possibly even surgery may be necessary to correct such an injury. Puncture wounds should be cleaned thoroughly, daily, with a dilute salt solution (one teaspoon of salt to one pint of warm water) or a dilute antiseptic solution. An old plastic syringe is useful to squirt the solution into the hole, to keep it clean and more importantly, to keep it open. A solution of hydrogen peroxide (one part to ten parts warm water) is very useful for cleaning a puncture wound. The use of a poultice is usually required a day or two after injury, to help draw out pus resulting from infection, especially if the injury location is on the sole of the foot.
Specially prepared powders containing antibiotics can be useful for application to fresh cuts or wounds to prevent infection. However, some powders can cause irritation which may stimulate the formation of proud flesh. Aerosol sprays containing antibiotics can help to dry up small wounds when fresh; horses generally do not like aerosols. When wounds are situated on parts of the body that are continually being moved, applying antibiotic powders or sprays dries the wound, but only makes it more likely to crack again when the animal moves, ultimately making the situation worse. In this case, it is preferable to apply an antibiotic ointment and bandage it in place. Pus coming from infected wounds or abscesses can burn and cause damage (in the form of dermatitis) in healthy skin nearby. This can be prevented by putting a protective layer of ointment on the skin, especially below the source of the discharge.
Injuries from kicks or blows cause bruising of the muscular tissue below the skin. For the first 24 hours, administration of cold treatment should help stop internal hemorrhage and reduce inflammation. After this, application of warm treatment for two to three days may help reduce the bruising and promote healing. If the skin has been broken, treatment as for a wound must be given.