When used as directed, Pasture-Mag 21 IGR will provide sufficient (S)-Methoprene insect growth regulator to prevent the emergence of adult horn flies from manure of treated cattle. Existing adult horn flies will not be affected. Start feeding before horn flies appear and continue use until cold weather marks the end of the horn fly season. Allow free choice to cattle. Cattle should consume an average of 0.8 ounces of Pasture-Mag 21 IGR per 100 lbs. of animal body weight per day, which is equivalent to 8 ounces per day for a 1,000 pound animal.
Provide access to fresh water and free-choice salt at all times.