Dairy cattle-Stable fly

Stomoxys calcitrans

Biology The stable fly is a very serious economic biting fly pest for confined cattle throughout the US and is becoming a serious pest for pastured cattle as well. Both sexes suck blood and prefer to feed on the lower body and legs of cattle. If enough flies are present, this may lead to reduced weight gains or milk production in dairy cows. Annual economic loss in North America due to stable flies is estimated at nearly $1 billion. Stable flies breed in many wet places, including old manure, decaying feed, calf bedding, compost, silage, etc. Stable flies will also disperse long distances from where they were bred and become significant pests of humans. The generally agreed upon economic threshold for cattle is 5 flies per leg, at which point beef cattle show reduced weight gains. Similar effects likely occur in milking cows. Management of stable flies is principally through improved sanitation and manure management. When sanitation measures are not enough to control adult populations, application of insecticides to premises or animal quarters may be necessary (see "Fly Control" section). There are a few on-animal chemical control options, listed below.

Management-chemical control

Ear tags

  • permethrin ear tag (GardStar Plus)-Apply one tag per ear on all animals when flies first appear in spring. Remove before slaughter.
  • zetacypermethrin/piperonyl butoxide ear tag (PYthon MagnuM)-Apply one tag per head of all animals at least 3 months old when flies appear in spring. Remove tag at the end of fly season or before slaughter.

Pour-ons, sprays

  • dichlorvos spray (Prozap Beef & Dairy RTU) Apply 1 to 2 oz per adult animal as a mist to wet hair. Use proportionately lower rates for smaller animals. Do not exceed 2 oz per animal per day. Do not soak skin or wet hide.
  • dichlorvos spray (Vapona)-Dilute 1 gal in 50 gal water (1% solution) and apply 1 to 2 fl oz of solution per animal per day as a fine mist spray. Do not wet hide. Do not treat calves under 6 months of age. Do not apply within 1 day of slaughter.
  • dichlorvos spray (Nuvan Fog5%)-Dilute 1 gal with 3.5 gal water (1% solution) and apply 2 fl oz of solution per animal as mist spray no more than once per day. Do not treat calves under 6 months of age. Do not apply within 1 day of slaughter.
  • dichlorvos/piperonyl butoxide/pyrethrins (Prozap VIP Insect Spray; Super II Dairy & Farm Spray)-Apply 1 to 2 oz to each animal, proportional to size. Do not soak the skin or wet the hide. Do not apply more than once per day.
  • diflubenzuron/permethrin pour-on (Clean-Up II; Lice-Ban)-Apply 3 mL per 100 lb body weight to maximum of 30 mL. Retreat as needed, but no more than once every 2 weeks.
  • octanoic acid/nonanoic acid/decanoic acid (Ecovet Fly Repellent)-Apply to hair coat with small sprayer or a cloth.
  • permethrin spray, ready-to-use (various manufacturers; 0.25%-1%)- Spray animal as directed.
  • permethrin spray, concentrate (various manufacturers; 10%-40%)-Dilute in water as directed. Spray animal as directed. Typical application interval is 14 days, as needed, but follow label.
  • permethrin pour-on (various manufacturers; 1%-10%)-Apply to animal as directed. Typical application interval is 14 days, as needed, but follow label.
  • permethrin/piperonyl butoxide spray, ready-to-use (various manufacturers; 1%)-Apply to animal as directed. Typical application interval is 14 days, as needed, but follow label.
  • permethrin/piperonyl butoxide spray, concentrate (various manufacturers; 10%)-Dilute in water as directed. Spray animal as directed. Typical application interval is 14 days, as needed, but follow label.
  • permethrin/piperonyl butoxide pour-on (various manufacturers; 1%-10%)-Apply to animal as directed. Typical application interval is 14 days, as needed, but follow label.
  • pyrethrin/permethrin/piperonyl butoxide spray (Raze) -Spray about 3 seconds per side. Repeat treatment when flies are troublesome.
  • pyrethrins spray (PyGanic Livestock & Poultry Insecticide)-Dilute at 9 to 14 oz per gal water. Apply 1 quart per adult animal to thoroughly wet hair. Repeat treatment each week as needed. Do not exceed 1 treatment per day. This organic product is OMRI listed.
  • pyrethrins spray (Evergreen Pro 60-6)-Dilute at 2 to 3 oz per gal water. Spray to wet hair thoroughly. Repeat treatment at intervals of 7 days, as needed.
  • pyrethrins spray (Lynx 1.4%, 5%; Tersus 5%)-Dilute in water as directed. Apply to wet hair thoroughly. Repeat treatment as needed, but do not apply more than once per day.
  • pyrethrins/piperonyl butoxide spray, ready-to-use (various manufacturers; 0.1%-0.5%)-Apply to animal as directed. Typically, treat daily as necessary but follow label for treatment interval.
  • pyrethrins/piperonyl butoxide spray, concentrate (various manufacturers; 0.96%-6%)-Dilute in water or oil as directed. Spray animal as directed. Typically, treat daily as necessary but follow label for treatment interval.
  • pyrethrins/piperonyl butoxide/N-octyl bicycloheptene dicarboximide spray (SSI-50)-Spray entire animal from two-foot distance as it's being released to pasture.
  • rosemary oil/geraniol/peppermint oil spray (Essentria IC3)-Mix 30 to 90 ml (1 to 3 oz) per gal mineral oil. Spray directly on animal in amounts to sufficiently cover.
  • rosemary oil/peppermint oil spray (Essentria All Purpose)-Mix 1 to 3 oz per gal water or mineral oil. Spray directly on animal in amounts to sufficiently cover.
  • thyme oil/2-phenethyl propionate/rosemary oil spray (EcoVia EC)-Dilute 0.5 to 1.5 oz per gal mineral oil USP. Spray to cover thoroughly. Repeat as necessary.

Backrubbers (oil)

  • permethrin (various manufacturers; 1%-40%)-Use undiluted or dilute in oil as directed. Recharge as needed.
  • permethrin/piperonyl butoxide (various manufacturers; 1%-10%)-Use undiluted or dilute in oil as directed. Recharge as needed.

Dusts

  • pyrethrins dust (Evergreen Pyrethrum Dust 1%)-Directly apply 2 oz to animal with shaker can or other device. Can be applied through dust bag placed in area where cattle congregate or pass through. This organic product is OMRI listed.
  • zetacypermethrin/piperonyl butoxide dust (PYthon)-Directly apply 2 oz per animal. Make sure to apply dust to legs. Repeat as needed but not more than once every 3 days.

Feed supplements (prevent development of flies in the manure of treated cattle)

  • diflubenzuron feed supplement (ClariFly 0.04%; ClariFly 0.67%; ClariFly 8%; JustiFly 0.67%; JustiFly 3%)- Mix into grain according to label to provide 0.1 mg ai/kg (4.55 mg/100 lb) body weight per day (follow table on label). Start feeding early in spring before flies appear and discontinue when cold weather limits fly activity.
  • diflubenzuron milk supplement (elim-A-fly Add-Pack with ClariFly 0.16%; JustiFly 0.16% Milk Replacer Product)-Mix daily into milk/milk replacer according to label to provide 0.1 mg ai/kg (0.1 oz elim-A-fly/100 lb) body weight per day. Start feeding early in spring before flies appear and discontinue when cold weather limits fly activity.
  • diflubenzuron salt supplement (JustiFly Fly-A-Salt)-Provide free choice with target consumption of 0.1 oz per 100 lb body weight per day. Offer 50 lb per 20-30 head of cattle. Feed from before flies appear until end of fly season.
  • diflubenzuron mineral tub (Vitalix ClariFly Tub)-Provide free choice with targeted consumption of 1.6 oz per 100 lb of cow per day (~one tub per 15-25 head). Provide before flies appear until end of fly season.
  • tetrachlorvinphos mineral block (Prairie Pride Rabon; Sweetlix Rabon Molasses)- Feed free choice, 1 block for 10-15 head of cattle (Prairie Pride) or 1 block for 5 head (Sweetlix).
  • tetrachlorvinphos feed supplement (Rabon 97.3; Rabon 7.76)-Include in diet or supplement at 70 mg per 100 lb body weight daily. See Mixing and Use Instructions for additional details.