Put Spot-On Products Out To Pasture

In our endless quest for victory in our battle with flies, a new weapon has come to the front. Our sprays, sheets, mists and masks are now joined by tiny vials of concentrated fly repellent we can dribble on our horses.

These new treatments come to us from the pet world–where once-a-month flea treatments are commonplace — and give us more ammunition to add to our arsenal of fly-wars products. But if you were hoping they would be the end-all answer, forget it.

Spot-treatment products belong in the pasture where their residual action can bring some level of comfort and peace to pastured horses or those left home alone all day while their owners are at work or school. It’s not that these products don’t work on stabled horses ?” they do. But horses that receive daily, hands-on care and grooming can be sprayed several times a day and often get sprayed again before riding and after being hosed off. Their barns and stalls can be kept relatively fly-free with good barn hygiene, reduced sunlight and fans. Frankly, fly sprays are better in these situations.

It’s the guys who are turned out that really need the continuous protection these spot-on products can provide. Some of our test horses were still quiet a week later, without their tails swishing and their feet stomping.

Unfortunately, we also found that the two-week products really don’t last 14 days. The effectiveness rises for a day or two, then slowly starts to wear off. Most of the spot-on fly repellents we tried tended to last five to seven days. To be honest, most packaging states the protection lasts “up to” two weeks. (One product in our test group, War Paint roll-on paste, can be reapplied after seven days.) Since most of these concentrated products cannot be reapplied for 14 days, other measures–like fly masks and sheets and occasional touch-ups with a natural fly spray–were needed on our test horses. Repeated applications (at two-week intervals) tended to increase the length of time the products remained effective.

All of the liquid drop-on products we tried contained 45% Permethrin as the active ingredient. Permethrin is a synthetic form of the natural, knock-down bug killer pyrethrin. Pyrethrin, which is extracted from the chrysanthemum plant, is effective repellent but not longlasting. Permethrin is the human-engineered version and it remains effective a lot longer than the natural form.

We tried several different spot-on fly products that each promised up to two weeks of relief from flies, mosquitoes and ticks. We found that most of these concentrated fly repellents, which you dot onto your horse’s head, withers, croup and legs, can provide relief from biting flies for days.

One misconception, or maybe it’s just wishful thinking, is that all flies will be killed on contact. That isn’t the case. Flies continued to buzz around the treated horses, some even lightly landing, but few remained long enough to bite. The nemesis of all horse owners: the giant “747s” or “C-5s” horse flies still hovered and attempted to land. Their mere approach sends most horses into a fit of tail swishing and bucking. But we felt the actual instances of landing and biting were probably lower on horses treated with these products.

There is precious little liquid (6-10 cc) in the tiny vials these products come in. But it’s potent, and the application instructions must be followed closely. That can be tough to do if the applicator isn’t easy to handle or clearly marked. One applicator we used was opaque, so there was no way to see how much product you were dispensing. (That particular product has since been discontinued, so we eliminated it from our final test results.)

The design of the applicator is important. We preferred the transparent or translucent plastic vials so you can see the level of the fluid as you’re dispensing it. We also wanted ones with cc markings in dark ink so they were easy to read. Be sure you can see the actual applicator before purchasing the package. (All of the ones in our test were in a blister pack or were visible through a window in the cardboard packaging.) The plastic vials on the two products from Star Horse Products, Celebration and Freedom 45, both had small caps so you could re-seal them, a nice feature if the application was interrupted and a safeguard against any liquid leaking out in the trash.

Some products called for 1cc to be applied on the forehead under the forelock. A few testers were reluctant to do this, fearing some of the liquid might run down into the horse’s eyes. Although we didn’t have any instances of this happening, we thought it was a valid concern. We did have problems with some of the liquids running down and off while applying them to the gaskin muscle or the front of knees. (Those that call for applying behind the knee were not a problem as we just lifted up the front foot.)

In many instances, we lost some of the tiny 1 cc amount that was supposed to be applied to each leg. In fact, we occasionally had a little run off at some of the other application sites, too. These shorted dosages could be the cause of some products not being as effective as possible.

Aside from incorrect dosages due to the difficulty of applying these drippy liquids to the legs, there is another major concern about runoff.Permethrins are toxic to cats. Most horse owners have barn cats around, so take care not to drip any of the liquid where cats might end up getting it on their fur. We’d even worry about drops that dried up, or fell onto blades of grass that a cat might chew on. These precautions are true of regular fly sprays, too.

A couple of horses in our test group had a temporary reaction at the site of application, so before dribbling one of these products all over your horse’s body, do a spot test first. If you don’t have any scruffing or hair loss after a day or so, it’s probably OK to use that product on that horse. Each product and each horse can be different, though, so do a small skin test first for each new product and each new horse.

The question of the safety of using these relatively new spot-on products over a long period of time remains open. There have been some concerns expressed about the long-term use of these highly-toxic chemicals on dogs and cats. There isn’t a lot of data out there about their use on horses.

And while manufacturers might say they are safe, permethrins, and even some of the “other” or “inert” ingredients not named on the labels could be absorbed through the skin because of the way in which these products are applied to the horse.

If you want to try a spot-on fly protection product, perhaps to give your pastured horses some measure of protection or to help your horse on a day-long trail ride where you can’t carry along a big bottle of fly spray, read the label carefully and apply the product in the amounts and locations suggested by the manufacture (never under the saddle.) And until more data about the effects of long-term use is available, we suggest you might want to confine its use to only the heaviest fly season and not use it any longer, or any more often, than necessary.

Bottom Line
We think these spot-on products can have a place helping pastured horses get some peace from the relentless onslaughts during the heaviest fly season. For horses kept up or ridden and bathed daily, we’d probably stick with barn sanitation and regular fly sprays. However, spot-on treatments may be the answer in barns that use fly predators, as regular fly sprays can’t be used around these tiny fly-killing wasps.

Of the products we tried, the one we liked best, both for its consistency and method of application, was War Paint. It’s not a true spot-on liquid but a paste in a container much like the ones that contain human antiperspirants.A dial on the bottom made it fairly simple to apply the exact amount the label dictated, and the sticky paste didn’t drip, run or soak down to the skin and it stayed put. It was also effective.

War Paint can also be applied again after a week, as opposed to two weeks for the other products. There are limitations on how much can be applied and how often, though. As with all of these products, read the label carefully before using it. War Paint doesn’t contain as high a level of permethrins as the liquid products, and it was the only product that had the chemical names of all of the “other” ingredients right on the label, which helps if your horse is sensitive to a chemical ingredient. Be aware, though, that if you’re going to be riding someplace where grooming counts, your horse will certainly look like he’s wearing, well, war paint.

Also With This Article
“Put It To Use”
“Long-Lasting “Spot” Fly Treatments”
“Fly-Control Product Articles”

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