Horse lovers welcome the warm air of spring. The days are getting longer and the horses are happily munching away in the pasture. Unfortunately spring and summer bring with them quite a few unwanted guests. Many different types of insects bother horses. Come to think of it many of the same bugs bother me. Especially when I’m taking a nap and they fly right above my ear. The difference is I have the ability to hunt them down and finish them with my handy dandy fly swatter while my horses must struggle to escape them day in and day out.
Flies tend to be one of the more persistent pests of horses. The dominant species in stables are the house flies and biting stable flies. Once outside, face flies, horn flies, deer flies and black flies become dominant. House flies do not bite, but, they can serve in the transmission of harmful microorganisms.
Basically, the pests be divided into three groups by their feeding habits. Sponging mouth parts, found on house flies and face flies, are used to sponge or sop up liquid foods. Stable flies, horn flies, horse flies and mosquitoes use piercing mouth parts to pierce the host animal's skin so that they may feed on blood. Some flies, such as bots and cattle grubs, have no mouth parts as adults. Stable fly bites are painful to both man and animal. When hungry, stable flies are quite persistent and will continue to pursue a blood meal even after being swatted at several times. Although the bite is painful, there is little irritation after the bite, and very few people exhibit an allergic reaction to stable fly bites. Other fly species that attack horses in pastures include horse flies and deer flies, black flies and other gnats,and mosquitoes.
Flies seem to live to reproduce. A typical life cycle of a fly is 21 to 25 days from egg to adult, and do they sure do keep busy! A female fly often lays twenty batches of eggs during her short life span, with each batch containing between 40-80 eggs. In fact, two flies can easily produce 1.8 million breeding pairs within just 12 weeks. All the more reason for horse owners to become vigilant in their fly control efforts.
Even if you employ the most diligent control efforts, including regular manure collection and disposal, you can expect flies and winged pests to be present on your farm. I've spent a lot of time researching and planning my counter attack this year. I thought I would share some of the recipes and links so you can develop a war strategy of your own :)
1. Fly Predators
I have decided to give Fly predators a try this year. My neighbor who owns the dressage facility next door has been ordering them for years and swears by them. She releases them two or three times each fly season into the manure pile and where they get to work right away. Fly parasites kill flies in the pupa stage before they hatch into flies. These are tiny wasps (the size of a fruit fly) that specialize in killing flies. They do not sting people or mammals. These insects are naturally occurring and widespread in low numbers. They just need reinforcement to exert fly control where fly breeding is abundant.
Fly predators are available from The Beneficial Insect Company in colonies of 10000-15000 insects. You can contact any of the companies that carry fly predators and they will work with you to determine the number of fly predators that you need. The number of fly predators needed based on the not only the number and type of animals that you have, but also the size of your pasture or stable and the conditions in your area.
2. Natural Fly Sprays
Pyrethrum? Pyrethroid? Permethrin? Cypermethrin? Tetrachlorvinphos? I counted a total of 57 different fly sprays in my horse supply catalog this month. So what are these chemicals we’re spraying all over our horses or misting throughout our barns? One of the most common ingredients found in many insecticides are pyrethrins. These poisons are extracted from certain species of the well known plant Chrysanthemum. Pyrethrins are effective insecticides and are fairly non-toxic to mammals, but one problem associated with pyrethrin use is the propensity of this extract to become allergenic. Contact dermatitis (blisters, rash or general irritation) is a common reaction in both humans and horses. People with sensitivity to ragweed or who have asthma can also be sensitive to pyrethrins, with symptoms such as sneezing, headaches, stuffiness, eye burning and itchiness. These products should not be applied near your horse’s eyes or other sensitive areas.
Pyrethroids are found as the active ingredient(s) in many fly and mosquito sprays, this class of man made chemicals are manufactured to produce the same type of chemicals found in chrysanthemums. Permethrin is a neurotoxin, a possible carcinogen (cancer causer), known mutagen (damager of genetic material), and suppressor of the immune system. It kills insects by over-exciting their nervous systems. In mammals, it also causes repeat nerve impulses which can lead to tremors, hyperactivity or paralysis. Because of the way they work, pyrethroids can also create problems for people taking medications for multiple sclerosis (MS). Given all these problems,I advise considering other options before using pyrethroids.
I started making my own fly spray last year and I was quite pleased with the results. The only downside is that in my experience the natural home made sprays don't have the same staying power as some of the store bought chemicals. It really hasn't been an issue for me as my horses stay in during the day in summer with evening turn out. I spray them twice a day with the homemade spray. In the morning and after dinner before turnout. I have included the recipe below. Be sure to spot test your horse before using.
Organic Fly Spray (½ gallon approx)
4 tbsp. Eucalyptus oil
4 tbsp. Citronella oil
1 pt. (4c) Apple cider vinegar
½ pt. (2c) Liniment or witch hazel
Fill remainder of ½ gallon container with water.
Apply as needed by spray bottle or wipe on
3. Protective Gear
Fly masks protect a horse’s eyes not only from these pests but also harmful UVA and UVB rays. For fly masks to be effective, purchase several and wash them regularly. If grit gets underneath or on the band, it can be very irritating to the skin. Do not buy ones pre-coated with pesticides. Also, do not leave the mask on continually; remove it at night.
If you own a horse with uveitis (moon blindness) I highly suggest purchasing a guardian fly mask. The Guardian Mask does a lot more than keeping the flies away. The sunshades provide 95% protection from harmful UV sun rays, allowing full visibility without compromising safety and comfort. This mask has made all the difference with my ERU Appaloosa Bailey. He is finally able to go out in the sun and graze with his buddies again.
Another mask I am considering this year is the "Quiet Ride" fly mask which was created for use underneath of the bridle. I have yet to try this product but I think its a great idea.
On cooler days, fly sheets can also protect not only against flies, but also pasture bleaching.
4. Common Sense
The rest is just a matter of common sense. One of the easiest ways to reduce fly populations is to eliminate the breeding habitat. They require organic matter, such as manure and bedding material, moisture and warm temperatures. The elimination of any one of these factors will minimize fly breeding. Clean stalls daily, remove stagnant water from troughs and scrub often, keep aisle ways cleaned up and don't let your manure heap get out of control. There are tons more products and ideas out there aimed at fighting flies. I include a few interesting links that I came across during my research below. I'm not sure if the "fly gun" is for real but it sure does look fun.