"It's winter and cold out, it's not a problem now!" I can hear many of us thinking. But this is exactly the time to start thinking about the basic causes of the inflammation process that triggers many forms of "the itches" and to begin your intervention tactics. A multi-pronged approach I first learned from Dr. Eleanor Kellon, VMD, well known leader and innovator in equine nutrition, has worked well for clients horses in the Southwest and across the country.
The basis of "itch", a sensation that causes the desire or reflex to scratch, arises from inflammation of nerves. Once sensitized, it becomes easier and easier for the nerves to become "excited" and more and more difficult to quell the sensation. The sensitivity may carry over from the original culprit (an insect bite or contact with a noxious plant or substance) so that almost anything becomes a "trigger" - something which will set off the need to scratch. Along with this comes a whole catalog of false-positive "allergies", even to substances the horse has never been exposed to before. A "true" allergy requires previous exposure to an allergy causing substance and the development of antibodies to the allergen itself, while a "false" allergy is an inflammatory reaction to a trigger acting as an irritant to the immune system.
Why some horses respond or react more to inflammatory insults than others isn't really known - just as why some people are allergic to bee stings or have autoimmune diseases and others do not. There may have been a reaction to midge bites or another "trigger" when their immune system was busy with something else and that began the process. What we need to accomplish is to support the immune system so it can effectively deal with future triggers. At the same time we don't want to "stimulate" the immune system as it is already overstimulated.
The first step in a comprehensive plan to combat next season's itchies is mineral balancing your horse's diet. Without the base diet in place to provide the body with the tools and building blocks to develop and maintain a strong immune system, all your subsequent interventions become an exercise in futility and a waste of your time and money. Start with a calcium phosphorus ratio as close as 2:1 as you can bring it, add magnesium to bring it to a similar level to phosphorus, then identify and balance excessive levels of iron (pro-inflammatory) and manganese.
The next step in your comprehensive plan is to provide a source of Omega-3 fatty acids and vitamin E in your horse's diet year round. When horses graze active gowing pasture they receive adequate Omega-3 but, as soon as hay is cut and cured this is lost almost immediately (along with vitamin E). Flaxseed (fresh ground or stabilized) at a rate of two to six ounces a day, flaxseed oil at one to four ounces per day, chia seed at two to six ounces per day or any of a number of commercial Omega-3 supplements can provide the powerful antioxidant support missing from hay. Vitamin E is another antioxidant which is easy to include (at a rate of 2 IU per pound of body weight or 2,000 IU for an average horse).
By starting these steps now when your horses may least seem to need them you're ensuring they enter into the critical spring shedding season with good immune system reserves.
A "nutraceutical" which has an anti-inflammatory effect is chondroitin sulfate. This is the "same" chondroitin popular as a joint supplement but given at a rate of 2.5 to 5 grams per 500 pounds body weight per day, or 5 to 10 grams per day for an average horse.
There are several other herbs and "natural" remedies which may be helpful but few will be effective once the inflammatory cascade has been set in motion. If you wait until your horse is already reacting to sweat and bug bites with hives or scratching themselves raw, you'll most likely need veterinary intervention and medications incluiding steroids and anti-histamines to slow down and halt the process and you - and your horse - will be stuck with another year of the misery of the itchies.
Caution! Just because sometihing is "natural" does not mean it is safe! Make sure your veterinarian is aware of any supplements, herbs and nutraceuticals you give your horse, especially if any medications or treatments are also needed. Even "natural" topical medications and sprays can be triggers - for example, a "natural" fly spray triggered my asthma last summer and raised hives on one horse's rump.
Plan ahead - and think about next summer's worst being a good roll in the sand and a shake after a ride. (This would be a great time to take Dr. Kellon's NRC Plus and Nutrition as Therapy courses!)
in very chilly Vail Az
I have included Wikipedia and commercial links here today because they provide some simple explanation.