Fly control has become an important component of livestock production across the nation. When it comes to prevention, it is beneficial to know your foe.
Horsefly: 25mm long, Deerfly: 6-10mm long
Strong fliers and females are biters
Deposit eggs (100-1000 at a time) in wet/moist habitats
Control: Animal - pyrethroid products weekly, but control is poor.
Environment - not effective since these flies do not rest on any one surface
6-9mm long, does not bite
Deposit eggs in fresh manure, garbage, lawn clippings, etc.
Rest on fences, buildings, trees and shrubs ñ often in the sun
Animal - usually not necessary since do not bite
Environment - remove manure, baits, pyrethroid sprays to resting sites
Deposit eggs on feed, decaying matter, old manure, moist hay
Cluster around feet and legs of livestock
Rest on shady surfaces such as fences, feedbunks, buildings and vegetation
Animal - pyrethroid sprays
Environment - clean around feed bunks, pyrethroid sprays to resting sites, fly baits will not work
Looks like house fly but slightly larger
Can travel several miles
Feeds on cattle secretions such as tears, saliva, nasal discharge and blood ñ commonly found on nose, face and backs of cattle
Deposit eggs in fresh manure
Spend less than 5-10 minutes per day on an animal, remainder of time spent on shaded vegetation
Vector of pink eye (Moraxella bovis) ñ physically scratch the eye with biting teeth
Control: Animal - insecticide sprays on face, mineral feeders with pyrethroid (de-lice) lining cover
Environment - impractical since must remove fresh manure
Small ñ 4mm long
Painful bite ñ can result in weight loss from irritation
Lay eggs in fresh manure (3 minutes old) and spend rest of life on backs of cattle
Highest numbers on bulls because testosterone attracts the flies
Animal - flies highly resistant to pyrethroid ear tags, best result is rotation of insecticides ñ topical pour-ons provide control for 1-4 weeks depending on weather and product used
Environment - not useful.