Evaluation of sunlight-exposed pyrethroid-treated netting for the control of face fly and housefly (Diptera: Muscidae).

BACKGROUND Face flies, Musca autumnalis De Geer (Diptera: Muscidae), and houseflies, Musca domestica L. (Diptera: Muscidae), have a significant impact on livestock and dairy production throughout North America. Pyrethroid insecticide efficacy can be affected by exposure to direct sunlight, and the rate of photodegradation is substrate and formulation dependent. Insecticide-treated netting (ITN) is finding new applications in crop and livestock production systems. A baseline study using long-duration no-choice assays has been carried out to gauge the effectiveness of ITN treated with β-cyfluthrin, λ-cyhalothrin and bifenthrin on face flies and houseflies. RESULTS After 12 weeks in direct sunlight, ITN treated with β-cyfluthrin was still highly insecticidal to face flies and houseflies, producing 100% mortality in petri dish assays. However, sunlight reduced the insecticidal activity of λ-cyhalothrin, with 3% of face flies and 50% of houseflies surviving after exposure to ITN that had been deployed for 10 weeks. Insecticidal activity was greatly reduced on bifenthrin-treated netting, with 20% of face flies and 50% of houseflies surviving in assays with netting deployed for only 3 weeks. CONCLUSION With careful choice of the pyrethroid applied, treated netting could be an important component of livestock integrated pest management programs focused on sustainable practices.