Beef Cattle, Face Fly and Horn Fly Control with Guardian Ear Tags, 1983

Guardian 5 and 7.5% (flucythrinate) ear tags were evaluated for face fly and horn fly control on beef cattle. May through Sep., 1983, in Montgomery Co., Va. Herds and treatments used in Test A were as follows: (1) Guardian 5% ear tags applied to 22 Simmental and mixed breed cows with calves and 2 Simmental bulls 24 May; (2) Guardian 7.5% ear tags applied to 20 mixed breed cows and calves and 1 Simmental bull 24 May; (3) standard Ectrin 8% ear tags appplied to 70 Angus cows with calves and 2 Hereford bulls 24 May; and (4) an untreated head of 15 mixed breed cows with calves and 1 bull. Guardian 5% and 7.5% treated cows, calves, and bulls received two tags per animal; Ectrin treated cows received two tags per animal and calves received one tag. All herds in Test A were monitored for 11 weeks. Herds and treatments used in Test B were as follows: (1) Guardian 7.5% improved design ear tags applied 17 Aug. to same herd as #1, Test a; (2) Guardian 7.5% improved design ear tags applied 11 Aug. to same herd as #2, Test A; (3) standard Ectrin 8% ear tags existing on same herd as #3, Test A; and (4) an untreated herd, same as #4, Test A. All Guardian treated cows, calves, and bulls received two improved design tags per animal; all remaining tags from Test A were removed. All herds in Test B were monitored for five additional weeks. Herds used in Test A and B were maintained in separate pastures and were situated within ca. 2 miles of each other. Weekly face fly and horn fly estimations were made by the same person on 10 adult animals per herd. Numbers of face flies were estimated on the face and head and horn flies on one side of each animal.