Effect of Using Either Synovex Primer or Synovex Choice Compared to Not Implanting on the Performance of Growing Steers

Authors

Sawyer D. Starrett, University of Nebraska-LincolnFollow
Rebecca L. McDermott, University of Nebraska-LincolnFollow
Sofia Suarez Lorences, University of Nebraska-LincolnFollow
Pedro Henrique Jota Fernandes, University of Nebraska-LincolnFollow
Dirk Burken, Zoetis Inc.
Jessica L. Sperber, University of Nebraska-LincolnFollow
Galen E. Erickson, University of Nebraska-LincolnFollow
Jim C. MacDonald, University of Nebraska-LincolnFollow

Date of this Version

2026

Citation

2026 Nebraska Beef Cattle Report, pages 29-30, MP-121, University of Nebraska Extension, 2026

Comments

Copyright 2026, Board of Regents, University of Nebraska. Used by permission

Abstract

Summary with Implications

A 120-day winter-growing study utilized 576 head of steers to evaluate three dry lot implant strategies on the growth of steers. The three implanting strategies included a non-implanted control, Synovex® Primer™, or Synovex Choice®. While on harvested corn residue fields, steers were supplemented with 4 lb Sweet Bran and 0.375 lb of a vitamin and mineral package. The targeted gain for the non-implanted control was 1.25 lb/d. Both Synovex Primer and Synovex Choice increased ADG over the non-implanted control cattle by 7.5% and 12.7%, respectively. Additionally, Synovex Choice had a 4.8% increase in ADG over Synovex Primer. Steer ADG increased linearly (P < 0.01) in a dose-dependent manner to increasing implant dose during the dry lot phase.