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Horse Fly Control For The Barn, Stable & Pasture

The temperatures are rising, the days keep getting longer and we all want to spend more time at the barn with our horses. Unfortunately, humans aren't the only ones itching to get out to the barn during this time of year. Flies are getting ready to make your barn their home.

Not only are these insects annoying, but they can spread disease. When flies bite your horse and feed on his blood, in serious cases, they can potentially cause digestive problems and even stunt your horse's growth. In order to protect both your horse and barn from fly infestation this year it's important to understand the fly life cycle.

Understanding the Fly Life Cycle

While many types of flies can bug your horse during spring and summer, you will most likely be dealing with house flies and stable flies.  These thrive around horse barns as they prefer horses and manure for both feeding and breeding locations.

The fly life cycle consists of four stages – egg, larva (maggot), pupa and adult. Most flies go from egg to adult in 2-4 weeks, with adult flies living 3-4 weeks. However, depending on the environmental conditions this lifecycle can be sped up.

Adult flies typically lay their eggs on fresh manure and moist organic material. Depending on the species the eggs hatch within 1-3 days and the larvae feeds on the manure where they hatched. The pupa stage is when the fly continues to develop its exoskeleton. After 2-4 weeks in pupa stage the adult fly emerges ready to bite our horses.

Effective equine fly control is accomplished by using a combination of control methods that target each stage of the life cycle.

Equine Manure Management

Manure piles are fly breeding heaven. Did you know the average 1000 pound horse generates 50 pounds of manure a day? Therefore, proper manure management is essential in the prevention of fly breeding.  Getting manure out of the stall as quickly as possible is the first step. You don't want to inadvertently create a fly breeding ground in your horse's stall. So, the more manure removed from the stall the less desirable area for egg deposition. Once you remove the manure make sure to store it as far away as possible from your barn.

Not only does manure in stalls need to be removed, but manure deposited in your pasture needs to be dealt with as well. Field deposited manure helps fertilize your horse's pasture, however it also serves as a fly breeding ground. Areas where horses congregate such as water troughs, shady areas, run-in sheds and gates should be cleaned weekly at a minimum to diminish fly breeding and control parasites.

In addition to picking your fields, you can also drag the fields to evenly distribute manure in a thin layer over a wide area. This will allow the manure to quickly dry out. As flies deposit eggs in the top few inches of moist manure, minimizing moist manure surface area is an effective fly reduction strategy. Flies cannot develop in dry environments, so spreading manure thinly is the first step in trying to break the fly life cycle.

Remember, it's easier and more effective to prevent fly breeding than to control adult flies. So the quicker you can remove their habitat, the less likely you are to see these pests.

Horse Fly Predators

Fly predators are nature's first line of defense in controlling flies. As horse owners are getting more and more concerned about products that are safe for use on their horses and the environment fly predators are gaining popularity. Fly predators are tiny non-stinging wasps that are part of a total farm fly control program. These wasps both lay eggs in the fly pupa as well as feed on fly larvae while it is in the manure around your farm. By eating the larvae fly predators break the fly life cycle. In addition, the eggs the predators laid hatch and naturally increase their predator population on your farm.

Although naturally occurring, fly predators are usually not found in large enough amounts to control the entire aggressive fly population at your barn. However it is because of the naturally occurring predators that without adding additional predators, your barn isn't consumed by flies.

So where do you get fly predators? Many companies sell horse fly parasites and will ship them to you. When they arrive all you have to do is open the bag they came in and dump the contents on a small manure pile at dusk. These nocturnal wasps will do the rest and neither you nor your horse will probably ever know they are around.

During horse fly season (April to September) fly predators should be replenished once a month. Although one release of predators can temporarily reduce the fly population it is important to apply predators more than once to ensure you have enough predators to attack the latest deposited eggs and their larvae.

Fly predators can travel up to 80 yards to find fly pupa and larvae to feed on. So, it's important to make sure you spread the predators around areas throughout your farm where manure and moisture prone areas are located.

Insect Growth Regulator (IGR)

Another way to break the fly life cycle is through feeding your horse a supplement containing Insect Growth Regulator (IGR). At Southern States we sell Pfizer Solitude IGR a feed-through horse fly preventative which, when mixed ½ oz into a horse’s feed daily will prevent house and stable fly development.

IGRs work by disrupting the pupa (molting) stage in the fly life cycle. Cyromazine, the active ingredient of Solitude IGR, safely passes through the horse's system and is excreted in the manure. The cyomazine prevents the new exoskeleton from forming properly, causing the insect to die and never reach adulthood.

Although it is nearly impossible to remove all potential fly breeding grounds from your farm, IGRs are a great way to help reduce the fly population. There should be a noticeable different in your fly population after 2 weeks of feeding an IGR and full results will be seen within four to six weeks of feeding the IGR.

Cyromazine has been safely used in horses since 2001.  Extensive research by the United States Department Of Agriculture USDA shows that Cyromazine is safe for horses, other mammals, beneficial insects, birds and fish.

If you are planning on introducing an IGR component to your fly prevention program, all horses on your property should be feed the Insect Growth Regulator for maximum effectiveness. Ideally feeding should start in later March prior to the beginning of fly season and continue until the first hard frost of the fall. However, regardless of when you start you will notice a reduction in your fly population.

Horse Fly Repellent

There are two types of fly repellent available to protect your horse from adult flies, spray on and feed through. There are a number of fly spray products on the market that can be used to repel and kill flies. Although these products can be pricey, you can use them to meet the fly protection needs of your individual horse.

At Southern States, we offer a variety of different fly spray for you to choose from ranging from standard chemical based to newer non-toxic herbal alternatives. Regardless of which type you choose be sure to read the label for application instructions. Remember fly spray needs to be reapplied as horses sweat, get wet and after exposure to direct sunlight as this can lower the effectiveness of the repellent.

An alternative to external fly repellent is to feed your horse an internal fly repellent. There are several products out on the market that have been specially developed to deter flies from landing on your horse or you can go with old fashion garlic and apple cider vinegar. Internal fly repellent works by having the horse secret oils that will repel flies and keep flies from biting.

As flies "taste" with their feet, only they will know the horse smells and therefore taste bad. Humans will not be able to notice the difference. It takes a while to build up this bad tasting effect so it is recommended that you combine internal with external fly repellent at the beginning of the equine fly season. When using feed through repellent it is not necessary for every horse on your property to be receiving it in their feed.

Horse Fly Spray Systems

A more comprehensive approach to fly repellent is to install an insect control system in your horse barn. The system automatically delivers a fine mist of insecticide at preset intervals throughout your facility. You can design the system to meet the needs and configuration of your barn to ensure that you have nozzles placed strategically over stalls, aisle ways or wherever you have an insect control problem.

Water-based and plant based insecticides can be used with the insect control system so you do not have to worry about potential toxicity affecting your horses, dogs, cats and people that inhabit your barn.

Once the system is installed it works 24 hours a day giving you peace of mind that regardless of whether or not you are at the barn, you are actively controlling your insect population. These systems are designed to be virtually maintenance free.

Equine Fly Gear

Regardless what fly prevention strategies you put in place there will most likely always be some bugs around your horse this Spring and Summer. If you have a horse that is especially sensitive to bug bites you may want to consider dressing them in equine fly gear.

A horse fly mask can be used to protect the horse's eyes from flies. Flies are attracted to the moisture around horses' eyes as well as goop that comes out of the horse's eyes. A fly mask can help prevent the flies from irritating not only your horse's face, but it can also help reduce the stress level associated with constant bugging by flies.

Fly sheets are another great clothing option for horses while they are turned out. Like fly masks, the tightly weaved material that makes up fly sheets prevents flies from being about to bite the horse through the material. Another benefit to both fly sheets and masks is not only do they protect your horse from pesky insects but they also protect them from harmful UV rays.

General Barn Keeping

Now that you have unleashed your fly prevention arsenal it's important to reevaluate your daily cleaning and maintenance around your horse barn. Make sure your garbage cans have tight fitting lids, lined with plastic bags. This will reduce odors and attract fewer egg laying flies. Also when possible try to keep your garbage as far away from the barn as possible.

Your horse feed room is another potential fly haven. Make sure you sweep out the feed room each day to avoid having spilled feed lying around. Store horse feed in a tightly sealed container or bin that won't let the odors out and will prevent flies from getting in.

Look around your farm for potential fly breeding grounds. Do you have rotting round hay bales, loose straw or hay, mulch or leaves? Clean them up! Flies love laying eggs in moist organic material and a little preventative measures up front can go great lengths when it comes to horse care.

There is no single fly control program that can completely eliminate flies from your barn, pasture area and horse, however using the tips above, understanding basic fly control and creating a fly management program for your barn can help reduce the population. Not only are horses happier when there are less flies, but they are healthier too.

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