Effective Fly Control

Effective pest control takes into account an insect's life cycle, how mobile it is, how it eats, and what it feeds on. These key characteristics are different for each of the flies that beef producers have to deal with. Proper identification of problem flies is the first step in selecting appropriate pest control strategies – and avoiding spending money on products or practices that have little chance of working.

Horn Flies

Scientists have estimated that horn flies cost the beef industry £100 million annually.

• About half the size of a house fly; biting-sucking mouthparts.
• Both sexes are blood feeders, eating (biting) 20-40 times per day.
• Eggs must be laid in very fresh manure; larvae develop in undisturbed manure; adults do not stray far from their host animal.
• Populations can rapidly climb to 1000 - 4000 flies per animal.
• Damage from reduced grazing, increased stress, and blood loss.
• Horn fly control commonly yields an extra 15-20 pounds of beef per weaned calf or stocker.

Control options include insecticidal ear tags, sprays, pour-ons, backrubbers and dust bags, and oral larvicides. While ear tags can be very effective against horn flies, they need to be managed properly to minimise insecticide resistance.

Additionally, the tags should be physically removed from cattle at the end of fly season. Other products applied directly to the animals need to be evaluated in terms of labour requirements, animal stress, and the ability of the operation to repeat treatment as often as needed for effective control.

Face or Autumn Flies

While often thought of as the second-most prevalent pest of pasture cattle, these flies cause far less damage than horn flies.

• Slightly larger than a house fly; sponge-like mouthparts with microscopic teeth
• Consume nectar; females also feed on animal secretions (tears, saliva, mucus, blood)
• Eggs in fresh manure
• Very strong fliers
• Primary economic damage from spread of pink-eye.

Since face flies spend so much time away from the cattle, they are difficult to control with insecticides. Most horn fly controls (ear tags and topical insecticides) have some level of effect on face flies. A good pinkeye prevention and treatment program is typically more cost-effective than trying to eliminate a high percentage of the face fly population.

Article provided by SDA Pest Control