Objective: The objective of this study was to compare LongRange to an insecticidal ear tag for horn fly control and determine the impact of weight performance on stockers when fly control technologies were used in combination with implants versus no implants.
Study Description: Crossbred stockers (n = 301; 587.82 ± 35.36 lb) were completely randomized by initial weight across 15 pastures. Pastures were randomly assigned to three different treatment groups: 1) one insecticide ear tag (Corathon; Bayer Healthcare, Animal Health Division, Shawnee Mission, KS); 2) LongRange injectable (Merial Limited, Duluth, GA); and 3) untreated control group. Within each treatment group, equal number of animals were randomly given either: Ralgro (Merck Animal Health, Madison, NJ), Revalor-G (Merck Animal Health, Madison, NJ), or no implant. Body weights and fecal samples were taken on days 0 and 90. Fly counts began 2 weeks after initial treatment and continued on a weekly basis until the end of the study.
The Bottom Line: The use of LongRange as a fly control technique adequately controls horn flies up to 10 weeks and exhibited the greatest weight performance in stockers (average daily gain: 1.60 lb) when used in combination with Revalor-G.
View full research report by authors S.S. Trehal, J.L. Talley, K.D. Sherrill, T.J. Spore, R.N. Wahl, W.R. Hollenbeck, and D.A. Blasi at http://newprairiepress.org/kaesrr.