How to Spray Cows for Flies

As spring ushers in calving and fresh green grass, it also brings with it dreaded biting flies. These pesky insects land on your herd, sucking blood from your cows and laying eggs in mucous membranes and open wounds. A heavy infestation of flies can result in eye infections, weight loss and even death in animals with compromised immune systems. Spraying your herd with topical fly products is a safe and effective way to minimize infestations and keep your herd happy and comfortable.

Things You'll Need

  • Grain
  • Pump sprayer
  • Permethrine-based fly spray
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Instructions

    • 1

      Herd your cows into a small paddock or corral. Moving your cattle into a smaller space makes it easier to spray each animal and keeps you from missing a stray cow. Pour a little grain or sweet feed on the ground to entice cows into the pen and keep them quiet as you work.

    • 2

      Pour a dose of permethrine-based fly spray into a gallon pump sprayer and fill to the top with water. Screw the lid on tightly and shake vigorously to mix. Pump the handle up and down to pressurize the sprayer, squeezing the trigger gently to make sure the sprayer is working properly.

    • 3

      Spray each cow with the fly spray. Start at the top of the animal's head and spray down along the spine, coating the hindquarters and tail thoroughly. Drenching the tail distributes extra spray along the body as the cow swats flies, extending the life of the spray and keeping flies at bay.

    • 4

      Respray the cows one a week from spring through the first frost. If the flies are extremely thick or aggressive around your herd, spray your cows as often as necessary to keep them comfortable and pest-free.