Fly Control for Horses and Cattle

During fly season, horses and cattle--whether in the barn or out in the field--are constantly under attack from flies. Besides irritating to the animals, flies spread disease. To prevent these problems, there areer several methods for killing or avoiding the flies. Be sure to carefully follow the instructions on all types of fly control to get the best results and prevent problems.
  1. Ear Tags for Cattle

    • Clip ear tags onto the ears of all cattle annually to drive away horn and face flies. Ear tags designed to repel insects contain insecticides. John Maas, DVM, of the University of California - Davis College of Veterinary Medicine recommends you switch between types of insecticides in the ear tags every year to avoid having the area flies develop resistance and to wait until the flies have already started hatching before putting tags on your cattle. If you do choose to use ear tags, remove them after fly season ends. This is another way to avoid developing resistance to the insecticide in the flies.

    Fly Sprays

    • Fly sprays are available for both horses and cattle. The recommended product can vary among species, though there are also some all-around fly sprays that can be used on horses, cattle and other species of animals. If you follow the instructions for application carefully, fly sprays can provide protection for several days at a time, depending on the product. These sprays work by applying an insecticide that the fly doesn't want to touch--so the flies are no longer willing to land on your horse or cow. Some fly sprays can even kill the flies that touch the chemical.

      You can also have fly-spray systems installed in your barn that release insecticide at pre-set times during the day and night. The insecticide kills off flies in the air.

    Pour-On Products

    • Pour-on products that you apply to specific body parts are available for both horses and cattle. These products come in applicator tubes that are opened and poured onto the skin, then left on. These products work by being absorbed and spread through the skin, so that the overall effect is similar to that of fly sprays where you are trying to avoid having the flies landing on your animal. Pour-on products must be reapplied as specified by the manufacturer.

    Feed-through Products

    • Products designed to be added to your animal's food that then move through the digestive system into the manure are also an option. After the manure is deposited into the pasture, the feed-through product prevents flies from laying eggs in the manure or by killing off the fly larvae when the eggs hatch. Since only the fly larvae are affected, feed-through products work best when used with other fly preventatives.

    Fly Predators

    • For a more natural method of removing flies from your property, consider fly predators. Fly predators are insects that eat the eggs or fly larvae, which decreases the number of flies on your property. Companies sell the fly predator eggs, which you then disperse about your property in areas prone to flies. Fly predator eggs need to be put out again several times each year. However, if you choose to use fly predators, be sure not to apply fly spray onto animals in the nearby area, since the fly predators will also be killed off by these products.