Got horses? Got bugs! More than just a nuisance, these irritating creatures are responsible for a range of conditions from leg or hoof concussions, caused by repeated stomping, to anxiety-induced weight loss, to an allergic reaction known as eosinophiliac granulomas—seen as a series of raised bumps on the chest, back, or belly. And that’s just for starters. At their worst, insects also are known to be carriers of more serious and even potentially deadly diseases, including West Nile Virus.
When you consider that just one female stable fly, which is estimated to produce 20 batches of 40 to 80 eggs each, that typically hatch within 21 to 25 days, will ultimately foster millions of offspring, it is a given that keeping the fly population under control is essential to maintaining the health and welfare of the horses in your care.
CONTROL INSECT BREEDING AREAS
Since manure and soiled bedding are the leading hotbeds for pests, chief among them stable flies, horseflies, deerflies, horn flies and mosquitoes, it is yet another reason to keep stalls and paddock areas as clean as possible. The rest of the barn needs to be kept clean as well. Remove uneaten grain ASAP, keep areas around water buckets and water tanks dry, and fix leaky drains or faucets, as these areas can all become prime breeding sites.
If properly handled, the nutrients passed out in manure and urine can be recycled into the pasture to become viable nourishment for vegetation. A ton of horse manure not only provides organic matter and important trace minerals, it is equivalent to 100 pounds of 14 nitrogen-5 phosphorus-11 potash, also known as 14-5-11 fertilizer. But, regardless of whether you plan to use it in the pasture or not, waste must be removed from the stable area, as prevention is the best protection.
If you do not have pasture space or choose not to spread or compost manure, you can create a temporary stockpile until it can be hauled away. There are collection services that specialize in manure removal, or you can make arrangements with a waste management company to take the manure along with your other garbage. Make sure you choose a holding site far from the barn or paddocks and away from running water.
Another option is to spread the manure daily. To do this properly, distribute it in a thin layer, then harrow it in to promote quick drying. The drying process helps to impede parasite eggs and larvae growth. As a cautionary note, horses should not be allowed to graze on the spreading area during that season, to make sure the parasites have been eliminated. Even if it looks like the manure has been absorbed, the ground could still harbor larvae and eggs.
Composting is often the most convenient and cost-effective manure management solution. With proper collection and management, manure transforms into dark, rich organic matter that is highly prized as a soil conditioner and nutrient additive.
Manure passes through three phases before the decomposition process is complete, which can take anywhere from a few weeks to several months depending on the nutrient values present in the manure itself.
Phase 1: Manure is composed of undigested food mixed with digestive juices and bacteria. When collected with organically based bedding, it often comes packaged with urine, and the combination becomes the medium that begins the decomposition process. At this stage, as the ammonia begins to form, turn over the manure and pack it down to create the right environment for bacterial fermentation.
Phase 2: The insoluble nitrogen in the feces is broken down to produce more ammonia, which in turn feeds the bacteria, which furthers the conversion process. The degree to which the manure becomes bio-available depends on the amount and type of feed the horses consumed, in addition to the age and health of the horses.
Phase 3: The bacteria release their remaining nitrogen, and the fiber, which has also finally decomposed, releases carbon dioxide and water to create the desired compost. If done correctly, heat from the composting process kills parasite eggs or larvae, and the process removes what was once the breeding ground for flies. Plus, the manure pile should shrink to about half its original size and become odor-free. It is now ready to be deposited on your pasture as fertilizer.
While prevention is the best means of pest control, some bugs will inevitably survive your efforts. What next? In addition to the multitude of fly masks and sheets designed to fend off pesky insects, there is also a wide array of chemical products that can be applied directly to your horses. When using either insecticides intended to kill offenders, or repellents developed to keep them away, follow directions carefully—the active ingredients are probably highly toxic. And don’t overdo it, since insects quickly develop immunity to chemicals. In addition, when used to excess, vapors from sprays or mists can irritate your horse’s respiratory system.
Here are several options from which to choose.
• Long-term insecticides are applied to areas in which flies tend to congregate, i.e., around feeders, water, or flat beams, and, depending upon the specific product, can be effective for up to six weeks.
• Fogs and mists are intended for daily use. They can be regulated automatically through a designated ventilation system.
• Chemical larvicides, in the form of dewormers, can be fed on a daily basis, or administered on a rotation schedule, to kill larvae from within.
• Baits such as traps, fly strips and sex attractants are useful in high traffic areas; electric black lights also are helpful.
For More Info
• Absorbine: Fly control products, www.absorbine.com
• Arbico Organics: Fly control fly eliminators, www.arbico-organics.com
• Bayer Animal Health: Fly control products, www.bayer-ah.com
• EPPS Biting Fly Trap by Horseline Products: Fly control equipment, www.horselineproducts.com
• Farmtek: Fly control products, www.farmtek.com
• Farnam: Fly control products, www.farnam.com
• Gene’s Pest Control: Fly control system, www.genespestcontrol.com
• Horse Fly Net: Fly control products, www.horseflynet.com
• Horse Health USA: Fly control products, www.horsehealthusa.com
• Horse Pal Fly Trap by Newman Enterprises: Fly control system, www.bitingflies.com
• Innovative Equine Systems: Fly control equipment and systems, www.equinesystems.com
• Mr. Sticky: Fly tape system, www.mrsticky.com
• Natures Balance Care: Natural insect control products,
• Nzi Biting Fly Trap: Cloth trap for capturing biting flies, www.nzitrap.com
• O2Compost: Aerated composting, www.o2compost.com
• Pfizer: Fly control products, www.pfizerah.com
• Pro-Tech Livestock Corp.: Fly control products, www.protech-control.com
• Pyranha Inc.: Insect control systems, www.pyranhainc.com
• Rincon-Vitova Insectaries: Fly control predators, www.rinconvitova.com
• SimpliFly: Feed-through fly control, www.simpliflyfeedthru.com
• SmartPak: Fly control products, www.smartpakequine.com
• The Source Biological Fly Control: Fly control predators, www.sourceecofly.com
• Spalding Labs: Fly control fly predators, www.sweetpdz.com
• United Spray Systems: Fly control system, www.automist.com
• United Vet Equine: Fly control products, www.unitedvetequine.com
• Valley Vet: Fly control products, www.valleyvet.com
BUGS BY REGION AND SEASON
The ferocity of biting and stinging insects has as much to do with the seasons as it does the regions in which they dwell. Take the Northern climes, for instance: winter conditions make for inhospitable environments to most external parasites, whereas in the South, where temperatures are higher and water is abundant, they are prevalent throughout the year. Then, as many insect populations migrate, diseases that have originated in one area can become a scourge in another, as in the cases of West Nile virus and Lyme disease. Therefore, as a stable owner or manager, especially with multiple horses in your care, you need to be aware of the parasites that inhabit your area and their life cycles.
In cold weather climates, chewing, biting or sucking lice and mites typically prevail year-round, although they are relatively uncommon. Both cause extreme itchiness, which can result in hair loss from rubbing. Mites are very hard to detect visually; you may need to call in your veterinarian for a proper diagnosis. But in both cases, if you find one horse that is infected, treat them all. Topical products work best—dusts, sprays and pour-ons, for example.
Spring parasites emerge early in the season in warm-weather regions, and in May or June in the North, with black flies leading the charge. In the larval stages, these pests live in fast-running streams. The weather warms and the ice melts rapidly, and this accounts for their seemingly sudden explosion.
Because it is not feasible to control these breeding sites, your best option is to protect your horses. Sprays or wipe-ons generally are not all that helpful. You can try applying baby oil inside their ears, but your best defense is to use fly masks and sheets. And, because black flies tend to stay out of dark or shady areas, be sure to have adequate shelter, or stable your horses during the day.
Spring also heralds the arrival of stable flies, which breed in fermenting hay piles and manure. The sooner you can get rid of waste or spread it out—no deeper than one inch for hay—the easier it will be to manage fly populations.
Ticks, another predominantly spring blight, appear at different times throughout the season depending on your location. Western regions are home to Rocky Mountain ticks, while the black-legged tick, the one responsible for spreading Lyme disease, appears in Northern regions in spring as well as fall. Because ticks feed on a variety of animals, including rodents that act as their first hosts, the best protection is to mow pastures regularly and avoid the woods. If a tick is found, it should be removed immediately.
Summer brings on a number of insects to join the stable flies that continue to be a management issue. Biting midges can cause “sweet itch” in predisposed horses. This is an allergic condition that results from the saliva infused in the bite as it penetrates the skin, and which causes a series of raised bumps that are itchy and irritating. Different regions are home to different species, but for most, they prefer to feed from sundown until dawn.
Mosquitoes also tend to feed at night. A nearly year-round problem in the South, they also present trouble in the summer in the North. There are hundreds of species and they gather in areas where water collects to breed. That is why it is virtually impossible to control them completely, and why it is necessary to vaccinate your horses for Eastern equine encephalomyelitis and West Nile virus before the carrier mosquitoes hatch.
Many species of horseflies and deerflies are at their height in the summer as well, with Northern regions experiencing a shorter season—June to August—than in the South, where they cause trouble from March to November. Pyrethrums can be used topically, and deep shady areas will help keep these flies away.
Fall brings relief to cold weather climates, as the fly population tends to die off as the temperature drops, but in warm weather climates, flies can re-emerge throughout the fall and winter months.
Even though it is a never-ending battle, owners and managers must be proactive in managing external parasites. For more information on how best to keep them under control, check with your local Cooperative Extension service, linked to your state university.