House Flies and Stable Flies on Livestock Farms
Fly control on farms is won or lost in the manure and wasted feed where larvae develop. Adulticide sprays alone select for resistance and do not keep pace with breeding. Sanitation, larval control, biological agents and targeted adult tactics form the working program.
Two different flies
The house fly (Musca domestica) is a non-biting fly that breeds in moist manure, spilled feed and decaying organic matter, completing egg to adult in about 7 to 10 days in warm weather. It is a nuisance and a neighbor-relations issue for poultry, swine and dairy units. The stable fly (Stomoxys calcitrans) bites cattle and horses, mainly on the legs, and breeds in wet mixtures of hay, manure and urine, especially around round-bale feeding sites and calf hutches. Stable fly pressure reduces weight gain and milk yield.
Resistance and the limits of sprays
House flies have developed resistance to organophosphates, pyrethroids, neonicotinoid baits and several larvicides wherever these were used heavily. Spraying adults treats the visible minority of a population while larvae in manure continue to emerge. Programs that last remove or dry breeding material weekly, use parasitoid wasps such as Spalangia and Muscidifurax, apply larvicides or biological agents where breeding cannot be removed, and reserve adulticides for peaks, rotated by mode of action.
Biological larval control
Entomopathogenic nematodes such as Steinernema carpocapsae infect insect larvae, and research has tested them in manure and litter. Results in fly breeding media are variable because manure chemistry, ammonia, moisture and temperature affect nematode survival. Vegalab's Larva BioControl contains S. carpocapsae and is currently labeled for crop and plant use. Premise use against fly larvae in manure and litter requires a label amendment and state acceptance and is in development.
Key facts
- Stable flies cost US cattle production an estimated 2.2 billion dollars per year (Taylor, Moon and Mark 2012, Journal of Medical Entomology 49:198)
- Manure management and biological control underpin poultry fly programs (Axtell and Arends 1990, Annual Review of Entomology 35:101)
- House fly resistance has been documented to most insecticide classes used against it (Scott et al. 2013, Pesticide Biochemistry and Physiology 107:377)
- Entomopathogenic nematodes, as macroscopic biological control agents, are exempt from FIFRA registration (40 CFR 152.20(a))
How our delivery technology applies
Nematodes applied to manure face desiccation, heat and ammonia within hours, and many die before finding a host. Encapsulation of infective juveniles in a hydrated biopolymer matrix can buffer moisture and slow release into the breeding medium. For volatile contact actives used as space or surface treatments, a shell extends residual. Both routes aim at the same problem: keeping the agent alive or active long enough to meet larvae emerging over days.
Dairy, feedlot and poultry operators can apply to host Larva BioControl manure trials.
Related reading
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