Vigilante is an insecticide used with both dairy and beef cattle to reduce the number of flies in an agricultural area. It is usually formatted as a 50-gram bolus containing 9.7% diflubenzuron,[1] an insect growth regulator which inhibits the formation of chitin and prevents insects from reproducing.[2] The bolus is administered via balling gun.[3] It is effective in reducing populations of horn flies and face flies for approximately 10–16 weeks.
Vigilante was originally produced by American Cyanamid, and was the first larvicide marketed as a bolus.[4] After the breakup of American Cyanamid, Vigilante was manufactured by Uniroyal Chemical and then by Chemtura.[5]
It is best used as part of an integrated pest management program in combination with other fly-control methods such as insecticidal tags, backrubbers, and periodic spraying.[6]