Location: Agroecosystem Management Research2021 Annual Report
OBJECTIVE 1: Determine the environmental predictors of stable fly outbreaks and dispersal. Subobjective 1A: Identify and model environmental variates associated with stable fly population dynamics. Subobjective 1B: Model stable fly population dynamics in differing climatic zones. OBJECTIVE 2: Investigate stable fly larval habitats to develop improved management strategies that protect livestock from stable flies. Subobjective 2A: Characterize the temporal and spatial dynamics of physical and biological parameters associated with stable fly developmental substrates. Subobjective 2B: Identify and develop stable fly larvicides and assess their sustainability. OBJECTIVE 3: Identify stable fly attractants and repellents for use in strategies to protect livestock from stable flies. Subobjective 3A: Identify novel stable fly attractant compounds from host animals and larval development sites (substrates). Subobjective 3B: Develop long acting formulations with spatial and contact repellency. Subobjective 3C: Identify and develop novel stable fly oviposition deterrents. Subobjective 3D: Incorporate products developed in 3A-3C into a comprehensive Push-Pull strategy for managing stable fly infestations and improving animal well-being.
Stable flies are among the most important arthropod pests of livestock and, with changing climate and agronomic practices, are poised to expand their roles as pests and disease vectors. Their painful bites reduce livestock productivity, annoy companion animals, and interfere with recreational activities. Recent estimates of the economic impact of stable flies on cattle industries in the United States exceed $2 billion. Current management technologies are unable to effectively manage stable flies. This project proposes to address the development of novel technologies for managing stable fly populations and their impact on livestock using basic and applied research. Basic research will address developmental biology and population dynamics. Applied research includes chemical control strategies, repellants for protecting animals, and attractants for improving the efficacy of trapping devices. Combined, these efforts will improve our ability to monitor stable fly populations, identify and manage larval developmental substrates, and protect livestock from their painful bites. Successful completion of this project will improve livestock productivity and producer’s profits, as well as reduce livestock stress and disease.
Progress has been made in most objectives with strong activities in furthering technology transfer development. For Objective 3, novel attractants associated with stable fly habitats were identified and further developed into a product with industry (Sub-objective 3A). Novel repellent blends in various formulations of coconut oil fatty acids were tested and demonstrated strong repellency against biting flies that attack livestock animals with over a week longevity in protection (Sub-objective 3B). These findings have attracted several U.S. small business companies to collaborate with USDA scientists to establish Cooperative Research & Development Agreements and secure funding from National Science Foundation and National Institute of Food & Agriculture small business grants. The developed attractants and repellent formulations were further incorporated into products (combined with other technologies) used for developing improved management strategies (Push-Pull), with preliminary results from a collaboration with stakeholders tested on cattle in pasture settings in Nebraska showed as effective as those from the traditional pesticide application against biting flies, but with only 1/3 of the costs (Sub-objective 3D). The identified stable fly repellent compounds also showed strong oviposition deterrence, with over 90% inhibition of female stable fly egg-laying in oviposition media treated with the repellent formulations (Sub-objective 3C and Objective 1). For Objectives 1 and 2, due to the pandemic shutdown and the retirement of one entomologist (mainly assigned to these objectives) partial objectives were completed; one of entomologists who performed this task retired in 2020 and the maximum telework hindered some field work required for some objectives due to the pandemic shutdown. However, starting from 2021 spring, substrates of the stable fly larval development habitats (hay feeding substrates) were collected, and samples were further extracted and DNA sequencies of microbial organisms were analyzed.
1. Attractant-impregnated adhesive stable fly tape. Stable flies are one of the most important arthropod pests of livestock that reduce cattle weight gain and milk production leading to annual economic losses in excess of $2 billion to the U.S. cattle industry. ARS scientists in Lincoln, Nebraska, have identified novel attractant compounds that can be used to reduce stable fly attack on cattle via mass trapping techniques. These attractants have been developed with adhesive technologies for stable fly control in feedlot to help cattle producers reduce stable fly infestation levels. A U.S. patent and an international patent application have been filed. A developed prototype product has been tested in the field resulting in improved protection of cattle against biting flies and over 80% reduction in cattle stress.
2. Development of coconut oil fatty acids and their derivatives as a universal insect repellent. ARS researchers in Lincoln, Nebraska, and Peoria, Illinois, have recently discovered free fatty acids and their derivatives associated with coconut oil as strong spatial and contact repellents against various blood-sucking insects including mosquitoes, ticks, bedbugs, biting flies as well as other nuisance pests. The repellent effectiveness of coconut oil fatty acids and derivatives was demonstrated as equivalent to the gold repellent standard, “N, N-Diethyl-meta-toluamide (DEET)”, plus coconut oil fatty acids and derivatives provide over week-long repellency. Working together with several U.S. small business companies, ARS scientists are developing several commercial products to prevent mosquito biting and their disease-transmission including repellent-impregnated textiles.
Zhang, S., Blore, K., Xue, R., Qualls, W., Cermak, S.C., Zhu, J.J. 2021. Larvicidal activity of natural repellents against the dengue vector, aedes aegypti. Journal of the American Mosquito Control Association. 36(4):227–232. https://doi.org/10.2987/20-6916.1.
Taylor, D.B., Harrison, K.E., Zhu, J.J. 2020. Methods for surveying stable fly populations. Journal of Insect Science. 20(6). https://doi.org/10.1093/jisesa/ieaa094.
Qualls, W., Xue, R., Farooq, M., Peper, S.T., Aryaprema, V., Blore, K., Weaver, R., Autry, D., Talbalaghi, A., Kenar, J.A., Cermak, S.C., Zhu, J.J. 2020. Evaluation of lotions of botanical-based repellents against Aedes aegypti (Diptera: Culicidae). Journal of Medical Entomology. 58(2):979-982. https://doi.org/10.1093/jme/tjaa244.
Ghosh, A., Zhu, E.V., Wang, H., Zurek, L., Zhu, J.J. 2021. Antibacterial activities of nepetalactones against public health-related pathogens. Natural Product Communications. 11(3). https://doi.org/10.1177/1934578X211004875.
Zhu, J.J., Roh, G., Asamoto, Y., Bizati, K., Liu, J., Harrison, K.E., Taylor, D.B., Lehmann, A.T., Otake, H. 2021. Development and first evaluation of an attractant impregnated adhesive tape against blood-sucking flies. Insect Science. https://doi.org/10.1111/1744-7917.12952.