Effects of 28-day Rotation of Monensin and Laidlomycin Propionate on Commercial Cattle Performance During the Growing Phase

Authors

Madison L. Bemisderfer, Kansas State UniversityFollow
Cody J. Schneider, Cornbelt Livestock Services, Rock Falls, IL
Logan R. Thompson, Kansas State UniversityFollow
Haley E. Larson, Kansas State UniversityFollow

Keywords

ionophores, growing heifers, performance

Abstract

Objective: Investigate the effects of multiple 28-day rotations of monensin (Rumensin 90; Elanco, Indianapolis, IN) and laidlomycin propionate (Cattlyst 50G; Phibro Animal Health Corporation, Teaneck, NJ) on growing commercial heifer performance.

Study Description: A total of 584 heifers (639 ± 57 lb initial body weight [BW]) were randomly divided among 10 pens at a commercial feedyard. All heifers were limit-fed a growing ration with treatment assigned as: 1) monensin (MON) included at 18.8 g/ton on a dry matter (DM) basis; or 2) 28-day rotation (ROT) of monensin (included at 18.8 g/ton on a DM basis) to laidlomycin propionate (included at 7.4 g/ ton on a DM basis) repeated twice during the 112-day trial. Performance was assessed with BW measurements every 28 days.

The Bottom Line: Rotating monensin and laidlomycin propionate every 28 days during the growing phase improved the performance of limit-fed beef heifers by 8.7% compared to consistent monensin feeding, indicating a label-compliant strategy with possible performance value.

Recommended Citation

Bemisderfer, Madison L.; Schneider, Cody J.; Thompson, Logan R.; and Larson, Haley E. (2026) "Effects of 28-day Rotation of Monensin and Laidlomycin Propionate on Commercial Cattle Performance During the Growing Phase," Kansas Agricultural Experiment Station Research Reports: Vol. 12: Iss. 1.