Taking a proactive approach to fly control helps avoid scenes like this—stable flies tormenting your cattle. (Photo by Dave Boxler, University of Nebraska–Lincoln Extension)
Taking a proactive approach to fly control helps avoid scenes like this—stable flies tormenting your cattle. (Photo by Dave Boxler, University of Nebraska–Lincoln Extension)

Potential fly outbreaks in feedlots are just around the corner. That means potential weight losses in cattle, the risk of disease transfer and complaints from neighbors.

Regular cleaning, monitoring and maintenance of typical fly-breeding habitats will help reduce fly populations in feedlots.

In general, a clean and tidy operation will have less fly problems than a messy one.

Fly populations are a mix of various lifecycle stages (egg, larva, pupa, adult). Therefore, control methods should be conducted regularly, preferably weekly, to effectively disrupt the fly lifecycle and help prevent fly outbreaks.

Typically, the main fly-breeding area in a feedlot operation is the area under and around feed bunkers where spilled and leftover feed is mixed with moisture and manure.

Cleaning up and removing spilled feed on a regular basis and providing concrete aprons around feed bunkers help prevent the accumulation of a suitable breeding habitat for flies.

The middle of pens where manure has been compacted by the cattle is relatively fly free, but the outside edges, corners and areas under fencing can all be sources of flies.

Runoff areas where water and manure drain into a catch basin are also main sources of fly breeding. Any method taken to encourage rapid drying or clean-up of these areas will be beneficial to fly control.

It is important to remember to manage other areas around the feedlot yard that may support fly breeding, such as manure piles, silage pits or silos, feed mixers and areas underneath augers where feed has spilled.

Writing a fly-management plan and communicating with neighbors about the actions you are taking to reduce fly populations on your operation will help avoid potential nuisance complaints.

Taking a proactive approach to fly control is your best defense. Identify sites where flies are breeding on your operation, locate the potential source of a nuisance fly outbreak and use a weekly clean-up and maintenance checklist to ensure the effective control of fly populations on your operation.

Recommended Control Methods

  • Stock pens at high density to compact and trample manure.
  • Remove spilled feed and silage weekly.
  • Enclose or fill in under feed bunkers.
  • Construct concrete aprons around feed bunkers and waterers.
  • Clean sick pens frequently.
  • Scrape and grade pens often, filling low areas and contouring for runoff.
  • Cover and store hay bales on dry land or raised pallets, or store hay in properly designed stack yards or hay sheds.
  • Minimize seepage from silage storage by covering and sealing edges of bagged silage and silage piles and cleaning around the base of tower silos.
  • Construct concrete curbs under pen fences and railings.
  • Raise bottom railings high enough to clean under.
  • Divert surface water by grading and providing drainage around pens and facilities.
  • Keep vegetation around the operation mowed short.

Additional Control Options

  • Place indoor and outdoor fly-bait stations at various locations.
  • Use residual insecticide spray on adjacent vegetation and buildings.
  • Mist for adult-fly control as needed (it is important to follow all label directions to ensure the safety of humans and livestock).
  • Treat with larvicides (check with your veterinarian, Extension entomologist or company sales representative regarding product options and usage).

For more information: http://www1.agric.gov.ab.ca/$Department/deptdocs.nsf/all/epw12257/$FILE/feedlots.pdf