Every beef operation is going to see its fair share of flies on cattle. However, the problem begins when horn fly populations exceed the economic threshold. But how many is too many? When left untreated, horn fly infestations can reach up to 4,000 flies per animal, staying on the cattle both day and night. However, studies have shown that at a level of even 200 flies per animal, your bottom line and animals will begin to see the effects.

Losses from horn flies cost the industry an estimated $1 billion each year due to the stress they inflict and cattle disease they spread, inciting weight loss as high as 50 pounds per yearling. Establishing a horn fly control plan and incorporating a feed through product like Altosid® IGR will reduce this stress and promote both healthy weight gains among cattle and healthy profits. Altosid® IGR has been proven to effectively control the biting pests and keep horn flies below the economic threshold.

Stay ahead of these horn fly populations by keeping an eye on the amount of flies you see on your herd. You’ll typically see horn flies clustered along the midline and spreading down the sides of the animal or on hot days, moving onto the cattle’s undersides. To most accurately estimate horn fly populations, check on your cattle in the morning while flies are still on upper sides of the animal.

Follow our “at-a-glance” guide below to easily evaluate horn fly populations on your operation to remain below the economic threshold.

Want to learn more? Watch our Tom McBeth discuss economic thresholds and his tips for controlling fly infestations.

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