Excessive fly populations can literally suck the profit out of your cattle operation. Biting flies reduce weaning weights, lower milk production and spread disease. Why should your hard-earned money go toward feeding flies? In today’s economic environment, it is more important than ever to keep fly populations in check to maximize efficiency and profitability.

Horn flies are the most economically significant fly that cattlemen need be concerned with. The horn fly alone is estimated to cause losses of over $800 million to the U.S. beef industry annually. The irritation and blood loss caused by biting horn flies can reduce calf weaning weights by 12 to 14 pounds and average daily gain in yearling steers can be reduced as much as 30 pounds during the grazing season. Horn flies also cause lowered sexual libido in bulls, resulting in reduced reproductive efficiency.

Horn flies alone have been shown to reduce weaning weights by an average of 20 lbs. per calf (weight loss can be highter!) Can you really afford to give that much money away with every calf?

Adult horn flies are dark gray and about half the size of the housefly. The life cycle is completed in 8 to 45 days depending on temperature and humidity. Horn flies tend to rest quietly on the back and shoulders of cattle until disturbed. Horn flies rarely leave their host except to lay eggs, to move to other cattle in the herd, or when cattle enter buildings. Most feeding occurs along the underline of the animal and results in scabby, often bleeding, sores. Each fly may feed from 10 to 40 times each day! Grazing time is disrupted, resulting in significantly reduced weight gains and daily production.

The methods to control horn flies are many and varied but most rely upon chemical control.

Ear Tags: Pesticide-infused ear tags have been widely utilized with success. However, this method requires the labor and stress of handling cattle twice - once to apply the ear tags, and another to remove these tags. Failure to remove ear tags as recommended has widely contributed toward development of pesticide resistance and has reduced the overall success of this method over time.

Adult horn flies rarely leave their host and take up to 40 blood meals per day!

Sprays and Pour-ons: Sprays and pour-on pesticides can also be effective; however they also require extra labor and handling of cattle. Another point is that they offer short-term control (one month or less). Therefore, in order for this method to offer optimum control, cattle must be handled and treated monthly throughout the fly season. Additionally, there is the fact that the applicator must handle these chemicals and the associated safety issues therein.

Backrubs: Some utilize backrubs laced with pesticides and oil. This method yields mixed results. It is difficult to get all cattle within the herd to properly utilize these rubs on a consistent basis. Additionally, labor is required to properly maintain these rubs to make sure they are not dislodged and contain effective levels of pesticides.

Feed-through Additive: However, one of the most convenient and effective methods of horn fly control involves self-fed mineral supplements and blocks. These supplements contain active ingredients that interrupt the horn fly life cycle, effectively reducing the overall population of horn flies. This method requires no additional labor and no cattle handling unlike the previously mentioned methods. Just provide self-fed mineral supplementation to cattle as you normally would.

STOCKADE^® branded fly control blocks, tubs and minerals containing either Altosid^® IGR or Rabon^® Oral Larvicide conveniently and effectively control horn flies. Both active ingredients act to disrupt the horn fly life cycle to prevent future generations of flies. Neither Altosid^® nor Rabon^® have slaughter withdrawal times and can be fed to all classes of cattle including nursing brood cows and calves.

STOCKADE^® Rabon^® Fly Control Blocks provide safe and effective fly control and require no additional labor or feeders.

For best results, start feeding STOCKADE^® branded fly control products at least 30 days before the projected last frost of the spring and 30 days after the first killing frost in the fall. In some areas, these dates will overlap. Horn flies emerge when average daily temperatures reach 65° F for a period of at least two weeks. Be sure to provide at least one mineral feeder or block per 10 to 20 head. Locate mineral feeders or blocks where cattle congregate (near watering, loafing or shade areas, etc.). Monitor consumption. Fifteen, 1000-lb cows should consume 50 lbs of mineral in roughly 2 weeks. Increase or decrease the number of mineral feeders or change locations if necessary to adjust for proper consumption. Remember that neither IGR nor ROL will kill adult flies. Use of approved adulticides will be necessary to eliminate adult fly populations when IGR- or ROL-containing supplements are introduced after adult horn fly infestation is already established.

In summary, horn flies represent a costly drain on profitability. Fly control is a must in these trying economic times in order to maximize efficiency and profitability. STOCKADE^® offers a variety of fly control supplements in different forms to allow producers to choose the option that best fits their cattle needs and management style. Call 800-835-0306 to learn about the STOCKADE^® fly control options available and how they can help improve profitability in your herd.

Altosid^® is a registered trademark of Wellmark International
Rabon^® is a registered trademark of Bayer HealthCare, LLC