Horn flies create both cattle welfare and economic challenges. Piperonyl butoxide is a synergist that is included in some pyrethroid formulations. It inhibits the breakdown of the active ingredient and is indicated to improve product effectiveness. Consider selecting pour-on pyrethroid products that contain piperonyl butoxide for improved fly control; if included piperonyl butoxide will be listed on the label. If a pyrethroid is used in a spray or rub, consider adding piperonyl butoxide to the mix. Searching for piperonyl butoxide online should result in a few product options; make sure the product label states it can be used on livestock.
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