Location: Agroecosystem Management Research
Title: Efficacy of cyromazine to control immature stable flies (Diptera: Muscidae) developing in winter hay feeding sites Authors
Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 14, 2011
Publication Date: April 18, 2012
Repository URL: http://handle.nal.usda.gov/10113/54102
Citation: Taylor, D.B., Friesen, K.M., Zhu, J.J., Sievert, K. 2012. Efficacy of cyromazine to control immature stable flies (Diptera: Muscidae) developing in winter hay feeding sites. Journal of Economic Entomology. 105(2):726-731. Interpretive Summary: In temperate regions, hay is frequently provided for cattle as supplemental forage during winter. When large bales are fed from stationary feeding sites, as is the normal practice in the central United States, accumulations of wasted hay mixed with manure and urine create an ideal substrate for the development of immature stable flies. These sites are considered to be primary sources of stable flies in the early summer each year. Both male and female stable flies bite cattle and other livestock to get the blood meals they need for mating and developing eggs. Their biting activity reduces the productivity of cattle and cost US producers more than $2 billion per year. No economically viable options for controlling stable flies in winter hay feeding sites have been available. In this study, we demonstrate that a single treatment with granular cyromazine can provide greater than 95% control of immature stable flies developing in winter hay feeding sites for an entire season. Cyromazine is an insect growth regulator that impedes cuticle formation in insects. Since vertebrates do not require cuticle, cyromazine is less toxic to them than table salt. Treating hay feeding sites with granular cyromazine requires very little labor and no heavy equipment. Control is economically viable with an estimated return of $10 to more than $50 for every dollar of cost.
Technical Abstract: The hay mixed with manure and urine residues at sites where hay has been provided as supplemental winter feed for cattle provide an excellent substrate for the development of immature stable flies, Stomoxys calcitrans (L.). Such sites are primary sources of early summer stable flies in the central United States and no effective measures are currently available to control fly development in them. A single application of granular cyromazine in May provided 97% reduction in the number of adult stable flies emerging from hay feeding sites. Stable fly control did not decline during the 12 wk season. A small decline in control was observed relative to anthomyiid, sarcophagid, and syrphid flies developing in the hay feeding sites. However, none of those flies are considered to be pests and = 50% control of those flies was maintained for 65 d after application. Cyromazine offers a safe and affordable option for the control of immature stable flies developing in winter hay feeding sites. Controlling those flies should reduce production losses attributable to stable flies which have been estimated to be in excess of $2 billion per year in the United States.