K-State Research and Extension

Objective: To evaluate the effect of two implants that have different lengths of effec­tive use on stocker cattle gains within an intensive early double-stocked native tall­grass prairie grazing system

Study description: Stocker steers (n = 281) were implanted with Revalor-G (Merck Animal Health, Madison, NJ) or Synovex One Grass (Zoetis, Inc., Kalamazoo, MI) and grazed on tallgrass native range for 90 days during the summer. The steers were individually weighed, after an overnight shrink, on the day of implanting, at midpoint of grazing, and the end of the grazing period. Total gains and average daily gain were evaluated.

Item	Revalor-G1	Synovex One Grass2	Standard error of the mean	P – value
Season long grazing
Initial weight (day 0), lb	554	567	6.0	0.10
Midpoint weight (day 44), lb	666	666	3.7	0.42
Final weight (day 91), lb	781	782	7.7	0.77
Average daily gain, lb	2.6	2.5	0.04	0.35
Body weight gain, lb	223	221	5.1	0.65
Gain from beginning of grazing through midpoint (day 0-44)
Average daily gain, lb	2.5	2.6	0.10	0.45
Body weight gain, lb	106	108	3.7	0.58
Gain from midpoint through end of grazing period (day 45 – 91)
Average daily gain, lb	2.6	2.5	0.10	0.47
Body weight gain, lb	119	115	3.1	0.48
1Merck Animal Health (Madison, NJ) implant treatment. 2Zoetis, Inc. (Kalamazoo, MI) implant treatment.

 The Bottom Line: Cattle performance was similar regardless of hormone amount and coating technology for these implants when used during a short duration grazing period with stocker steers.

View full research report by authors J. K. Farney and M. E. Corrigan at https://newprairiepress.org/kaesrr/vol5/iss1/.