Q: “What about drugs, magnets or exercise to stimulate circulation in the hoof?”
—New Mexico farrier
A: “As a farrier, I am not current on all of the drug therapy used to increase or restore blood to the foot, but some alpha blockers like carbocaine, phenoxybenzomine and acepromazine, when injected into the digital arteries or around the palmar nerves, have been shown to relax the muscular sphincters of the a/v shunts, thus restoring normal blood flow.
“Drugs like bute and aspirin have an anti-platelet effect in the vessels, thereby decreasing the micro thrombosis that sometimes clog things up. Nitroglycerine can be applied directly to the digital arteries via a transdermal cream and has been shown to be a powerful vasodilator, but none of these drugs in my experience has had miraculous results.
“I think the jury is still out on the use of magnets. I have not seen any credible scientific data to substantiate the claims of magnet manufacturers, not to say they do not exist. Generally, I don’t think we know the exact mechanisms of how or why magnets may work. It is, though, well documented that exercise increases both the core body and peripheral blood profusion. During aerobic exercise, a wide variety of naturally occurring vasodilators are released into the blood that have been shown to increase circulation to the periphery. But often, lame horses don’t get a lot of exercise. I personally am a big proponent of hand walking on a daily or twice-daily intervals if at all possible.
“Another method I am aware of is to increase or restore blood flow to the foot is the coronary grooving procedure. This procedure has been shown to affect dorsal wall growth rates in the foundered horse, an indicator of increased blood flow.
“Keep in mind that although one may be able to influence blood flow to the foot by a variety of methods, if there are mechanical reasons for vessel blockages like coronary shunting, heel impingements, pinched laminar or coronary arteries due to sheared or underslung heels or P3 displacement, all the magnets or drugs in the world won’t likely help. What may be needed in these cases is sound horseshoeing which includes support and protection.”
—Mitch Taylor, Kentucky Horseshoeing School, Mt. Eden, Ky.
(For more information on coronary grooving, refer to page 68 in the January/February, 1998 issue of American Farriers Journal.)
A: “There are several situations in which the use of drugs and exercise are useful to help establish or improve circulation in the hoof, not the least of which is laminitis. As for the use of magnets, I think school is still out on the efficacy of magnets in treatment of any kind.
“In any case, it is always best to consult a professional before instituting any treatment, especially drug therapy. Exercise should be done with consideration paid to the limitations of the horse. However, I believe exercise is the best, least invasive option for improving circulation.”
—Paul Melcher, Livonia, Mich.
A: “Personally, I haven’t had much experience with magnets, although I know people who use them and swear by them. They put them in pads and blankets, even on themselves. But I don’t use them in my practice.
“I’m not a big advocate of drugs. I leave that for the vets. Usually, when clients are asking about drugs or magnets, they either heard about it or read an article and want me to give it a try.
“As far as exercise goes, horses that are exercised daily have more hoof growth than those who are exercised once a month. Exercise stimulates growth. If there’s more circulation, there’s going to be more growth.
“But it all comes down to good, solid, basic shoeing. One of the hardest things to get back to is basics. Most problem horses really just need a good shoeing job. It’s the best thing for them.
“My ‘secret’ to keeping the foot healthy is correct shoeing and trimming. It may seem plain and simple, but more times than not, those horses stay sound. ”
—Eric Novaez, Seguin, Texas