Now is the time to map out your fly control program. Horn flies normally begin showing up in spring when average daily temperatures reach 65º F for a period of two weeks.  They remain a nuisance until cool weather in late fall or early winter.  Here are four quick tips to help you develop an integrated management program for controlling horn flies in your cattle enterprise:

1. Clean and remove fly breeding media in confined areas.
2. Use premise sprays to kill flies in shelter and shade areas.
3. Use pour-on, spray-on, or rub-on insecticides, insecticide dusts, or ear tags to control adult flies on animals.
4. Use feed or supplemental mineral products containing an Insect Growth Regulator (IGR) such as Altosid® (brand name for methoprene).  This type of feed additive passes through an animal’s digestive system relatively unchanged.  It remains effective in the manure, where it stops development of immature horn flies before they emerge as adult flies.

Altosid is available in select Purina products with the MTH designation.

These products are available as both free-choice minerals and Cattle Chow products.

Feed and supplemental mineral products that contain Altosid work best if they are fed in spring prior to the appearance of flies and continued until cold weather restricts fly activity in late fall.

Source:  Purina Mills