MS-MR-2-Horse Tales pests21Ask anyone who keeps horses — or any other form of livestock, for that matter — about one of the most important aspects of keeping your animals happy and healthy. One of the answers you’ll undoubtedly get will have to do with pest control.
No matter what the season, uncontrolled pests can wreak havoc on your farm and livestock. The most important part of a good management program is to be pro-active, before the pests become a major problem, and utilize good sanitation procedures.
Shoo fly!
There are many different kinds of flies and insects that affect horses. Not only do insects cause irritation and physical discomfort to our horses, but they also carry disease. Other non-biting flies cause problems when their larvae are ingested and hatch internally, causing damage to the horse’s stomach and intestines. Being pro-active before a problem exists is the easiest way to keep your horses happy and healthy.
Controlling the immature stages of insects (the eggs, larvae and pupae) is much easier than attempting to control the adult population, which multiplies rapidly and becomes a nuisance. The immature stages thrive under moist conditions — in manure, wet and soiled bedding, spilled and wet feed — for 10 to 21 days. Clean your stalls on a daily basis and wipe up spilled or wet feeds immediately. Keep alleyways and other areas clean of manure and debris. Inside the barn, you can hang flypaper or sticky tape to catch flies and other insects, replacing when necessary.
Follow a good manure management program; manure and soiled bedding can be spread to dry out quickly and kill eggs or larvae that may be present.
Puddles and mud mixed with manure can provide an ideal breeding ground for insects. Check under and around watering and feed troughs for trouble spots and use sand, fine gravel or soil to fill in low areas that tend to puddle up, both inside and outside the barn.
IPM, or Integrated Pest Management, is an environmentally sensitive approach to pest management that relies on a combination of common-sense practices. It utilizes information on the life cycle of pests in combination with the least-risky pest control methods. With the problems that beekeepers are finding across the country, resulting in the deaths of honeybees that are critical to vegetable, fruit and flower growers, horse owners will want to use caution before employing the use of broadcast spraying of these non-specific chemicals.
In recent years, there have been a number of companies offering naturally occurring biological control organisms, such as fly predators and parasitoids. Commonly called “fly parasites”, the most effective parasitoids are wasps or flies that attack only a particular stage of one or several related species of pest flies. The immature parasitoid develops on or within the targeted pest, feeding on its body fluids and organs. They are not harmful to livestock or humans.
The use of physical barriers, such as fly masks, fly sheets and leggings will help protect your horse and improve his comfort. Fly masks are sold in a variety of sizes and styles; some can even be used with a bridle while you are riding. As with any other article of tack, you’ll want to measure your horse and make sure the mask or sheet fits properly. These physical barriers should be removed each day after turnout; check for irritation, signs of rubbed hair or injury underneath, and wash when necessary.
An important part of an integrated pest management program includes fly sprays used on your horse, space sprays for enclosed areas, and baits. Do check the label to be sure the product is safe to use around horses and other animals, and that it does not contaminate water supplies or pose a threat to the environment or to any predator flies or other biological controls you might be using. Fly bait traps can also be effective for low or moderate fly problems.
Utilizing several different types of pest control in an integrated pest management program will go far in helping to keep fly and insect populations under control.


Keeping rodents at bay should also be high on your to-do list. Mice and rats not only can multiply amazingly fast — and eat a significant amount of feed in the process — but they can harbor and pass along diseases, such as salmonella, leptospirosis and rabies to other animals, and humans as well. The gestation period for mice and rats rages from nine to 21 days; with each female producing litters of five or six babies up to 10 times each year. These progeny mature by the time they are just three months of age. A rule of thumb is, if you see one mouse or rat, there are probably 25 more that you don’t see. Figuring in all these hungry vermin, 100 rats can consume a whopping amount of feed in a year — more than one ton, which is about the amount of feed that a standard size adult horse eats. Add in how much feed is ruined from the droppings and urine of these creatures, and you’ve got a very good reason to be diligent in your efforts to eradicate the problem!
The best way to start a good rodent control program is to be sure that all feed, supplements and other foodstuffs are kept in rodent-proof containers. Best are steel bins or cans with tight-fitting lids that can’t be chewed (no matter how strong you think that plastic garbage cans are, rats and mice will chew through them in no time!)
Clean up any spilled feed immediately, wiping the area with a damp rag. Keep your feed room clean — free from piles of old rags, blankets, feedbags or other materials that provide ideal nesting material. Store tack, especially blankets, covers and sheets separately from where you keep your feed and hay to discourage rodents from chewing and causing damage. Remove any garbage that may be present.
If you’ve noticed rodent droppings or chewed ‘nests’ of material, sanitize the area by picking up and sweeping the floor, followed by a wash of water with bleach or other sanitizer, following dilution and directions on the label.
Check your tack room and feed room and repair or replace loose or broken boards; broken or cracked windows; holes in floors or siding. Put up screening or hardware cloth over vents, remembering that mice can squeeze through a hole that is just 1/4 inch in diameter! You can use calking to fill up cracks in your foundation or around windows.
Keep grass and shrubbery trimmed and away from the sides of your barn, as they provide ideal hiding places for rodents, as do wooden boards and other debris that may have been leaning up against the side of the barn.
Now that you’ve done your diligence in repairing and sanitizing the areas of your barn that contain your feeds and tack, you’ll need to work on eradicating any rodents that may be present, and prevent new ones from taking up residence.
Barn cats have long been utilized for rodent control. A few good ratters can be invaluable; but it is important to keep the cat population from spiraling out of control as well. Have your cats spayed or neutered; or consult with your veterinarian about controlling unwanted litters by the use of feline oral contraceptives.
Some barns utilize various types of rat poison, however if there are cats, dogs and small children around, this should not be an option. Traps can be used very effectively, as you can easily remove and dispose of the carcasses of the trapped animals. In addition to the old-fashioned single snap traps, there are large live traps which use already trapped mice to attract others. These can hold a number of mice, and can be set about 10 feet apart along the base of walls where there is an active population of rodents.
In addition to rats and mice, it is also important to keep other vermin, such as opossums, away from your barn and premises — as the opossum is the definitive host for the protozoa S. neurona, which causes most cases of the deadly EPM, or Equine Protozoal Myeloencephalitis. Though the disease is not fatal to opossums, horses can ingest the protozoa from contaminated feed, hay, water or pasture. Often, an opossum can come along and eat from a horse’s feed bucket that has been left on the ground; buckets should be removed or at least turned over after the horse has finished eating his food. If you feed barn cats or other pets in or near your barn, pick up uneaten food and store in a container with tight fitting lid. As with rodents, the key is prevention.
Eradicating any nuisance animals, along with using good sanitary procedures and blocking access to pests will go a long way in keeping your horse in good health and condition.