• Skip to primary navigation
  • Skip to main content
Texas and Southwestern Cattle Raisers Association

Texas and Southwestern Cattle Raisers Association

To Honor and Protect the Ranching Way of Life

  • Home
  • Who We Are
    • Why Join
    • Leadership
    • Staff
    • Partners
    • FAQs
    • Newsroom
    • Sponsorships
    • Employment
  • What We Do
    • Theft and Law
    • Issues and Policy
    • Education
    • Students and Young Professionals
    • The Cattleman Magazine
    • Disaster Relief Fund
    • Cattle Raisers Insurance
    • Cattle Raisers Trading Co
  • Events
    • Cattle Raisers Convention
    • Policy Conference
    • Summer Meeting
    • Ranch Gatherings
    • Ranching 101
  • Join
  • Member Center
  • TSCRA Store
  • Show Search
Hide Search

Cow-calf Corner: What implants can I use for finishing cattle on my operation?

Paul Beck, Oklahoma State University, Extension State Beef Cattle Nutrition Specialist

Over the last few weeks I have been describing the new rules from the FDA regarding reimplanting beef cattle. Last week I showed the implants labeled for use during the stocker and “Growing Calves in Drylot” phase of production. 

The new FDA rules affect the use of implants in grower/starter yards and finishing operations the most. Look for new implant programs and approvals for products in the near future to address these rulings.

The FDA provided a list of currently approved and marketed implants available. 

(From: https://www.fda.gov/animal-veterinary/product-safety-information/fda-provides-list-currently-approved-and-currently-marketed-implants-available-beef-cattle-target )

Here is the list:

Growing Beef Cattle Fed in Confinement for Slaughter

Implant NameApproved useApproved for Reimplant in this class
Component TE-IS w/ Tylan‡
(trenbolone acetate and estradiol and tylosin tartrate implants)
For increased rate of weight gain and improved feed efficiency in growing beef steers fed in confinement for slaughterNo
Component TE-IH w/ Tylan‡
(trenbolone acetate and estradiol and tylosin tartrate implants)
For increased rate of weight gain in growing beef heifers fed in confinement for slaughterNo
Component TE-200 w/ Tylan‡
(trenbolone acetate and estradiol and tylosin tartrate implants)
For increased rate of weight gain and improved feed efficiency in growing beef steers and heifers fed in confinement for slaughterNo
Compudose
(estradiol extended-release implants)
For increased rate of weight gain and improved feed efficiency for up to 200 days in growing beef steers and heifers fed in confinement for slaughterNo
Encore
(estradiol extended-release implants)
For increased rate of weight gain and improved feed efficiency for up to 400 days in growing beef steers and heifers fed in confinement for slaughterNo
Ralgro
(zeranol implants)
For increased rate of weight gain and improved feed efficiency in growing beef steers and heifers fed in confinement for slaughterNo
Revalor-IS
(trenbolone acetate and estradiol implants)
For increased rate of weight gain and improved feed efficiency in growing beef steers fed in confinement for slaughterNo
Revalor-S
(trenbolone acetate and estradiol implants)
For increased rate of weight gain and improved feed efficiency in growing beef steers fed in confinement for slaughterNo
Revalor-XS
(trenbolone acetate and estradiol extended-release implants)
For increased rate of weight gain and improved feed efficiency for up to 200 days after implantation in growing beef steers fed in confinement for slaughterNo
Revalor-IH
(trenbolone acetate and estradiol implants)
For increased rate of weight gain in growing beef heifers fed in confinement for slaughterNo
Revalor-H
(trenbolone acetate and estradiol implants)
For increased rate of weight gain and improved feed efficiency in growing beef heifers fed in confinement for slaughterNo
Revalor-XH
(trenbolone acetate and estradiol extended-release implants)
For increased rate of weight gain and improved feed efficiency for up to 200 days after implantation in growing beef heifers fed in confinement for slaughterNo
Revalor-200
(trenbolone acetate and estradiol implants)
For increased rate of weight gain and improved feed efficiency in growing beef steers and heifers fed in confinement for slaughterNo
Synovex C
(progesterone and estradiol benzoate implants)
Synovex C is only approved for use in growing beef steers fed in confinement for slaughter when it is used as part of a reimplantation program with Synovex S (see next column).Yes

Synovex C is approved for increased rate of weight gain in growing beef steers fed in confinement for slaughter in a reimplantation program where Synovex C is the first implant and a Synovex S implant is administered approximately 70 days later.
Synovex S
(progesterone and estradiol benzoate implants)
For increased rate of weight gain and improved feed efficiency in growing beef steers fed in confinement for slaughterYes

Synovex S is also approved for increased rate of weight gain in growing beef steers fed in confinement for slaughter in a reimplantation program where Synovex C or Synovex S is the first implant and a Synovex S implant is administered approximately 70 days later.
Synovex H
(testosterone propionate and estradiol benzoate implants)
For increased rate of weight gain and improved feed efficiency in growing beef heifers fed in confinement for slaughterNo
Synovex One Grower
(trenbolone acetate and estradiol benzoate extended-release implants)
For increased rate of weight gain for up to 200 days in growing beef steers and heifers fed in confinement for slaughterNo
Synovex Choice
(trenbolone acetate and estradiol benzoate implants)
For increased rate of weight gain in growing beef steers fed in confinement for slaughter and for increased rate of weight gain and improved feed efficiency in growing beef heifers fed in confinement for slaughterYes

Synovex Choice is also approved for increased rate of weight gain for up to 200 days in growing beef steers and heifers fed in confinement for slaughter in a reimplantation program where Synovex Choice is the first implant and a Synovex Choice, Synovex Plus, or Synovex ONE Feedlot implant is administered 60 to 120 days later.
Synovex Plus
(trenbolone acetate and estradiol benzoate implants)
For increased rate of weight gain and improved feed efficiency in growing beef steers fed in confinement for slaughter and for increased rate of weight gain in growing beef heifers fed in confinement for slaughterYes

Synovex Plus is also approved for increased rate of weight gain for up to 200 days in growing beef steers and heifers fed in confinement for slaughter in a reimplantation program where Synovex Choice is the first implant and a Synovex Plus implant is administered 60 to 120 days later.
Synovex One Feedlot
(trenbolone acetate and estradiol benzoate extended-release implants)
For increased rate of weight gain and improved feed efficiency for up to 200 days in growing beef steers and heifers fed in confinement for slaughter Yes

Synovex One Feedlot is also approved for increased rate of weight gain for up to 200 days in growing beef steers and heifers fed in confinement for slaughter in a reimplantation program where Synovex Choice is the first implant and a Synovex One Feedlot implant is administered 60 to 120 days later.

My take home messages from this list:

1)   Ralgro is approved for the preweaning “Beef Calves”; “Growing Beef Cattle on Pasture” and “Growing Beef Cattle Fed in Confinement for Slaughter” stages as well, but has no reimplant label claims. 

2) Synovex-S and Synovex-H are only approved for “Growing Beef Cattle Fed in Confinement for Slaughter”.

3) Until the finishing phase of production both Compudose and Encore are only approved in steers.

4) All Component brand implants containing Tylan (Elanco Animal Health products) will now have to be approved and scripted by a veterinarian due to the VMD ruling.

5) The only implants labeled for reimplanting during finishing are Synovex brand implants and these reimplant labels are very specific regarding products and timing of reimplanting cattle.

Here are some resources available for further information: https://www.fda.gov/animal-veterinary/resources-you/fda-letter-industry-provides-additional-information-and-clarification-use-beef-cattle-ear-implants#1

Written by:
Jaclyn Roberts
Published on:
August 9, 2023

Categories: TSCRA Update

Recent Posts

Crime watch: Brangus bull missing in Fayette County

June 13, 2025

Texas & Southwestern Cattle Raisers Association Special Ranger Kenny Murchison, District 20 in …

Continue Reading about Crime watch: Brangus bull missing in Fayette County

Crime watch: Cattle missing in Freestone County

June 13, 2025

Texas & Southwestern Cattle Raisers Association Special Ranger Chace Fryar, District 21 in East …

Continue Reading about Crime watch: Cattle missing in Freestone County

Crime watch: Charolais bull missing in Luling

June 13, 2025

Texas & Southwestern Cattle Raisers Association Special Ranger Robert Fields, District 25 in …

Continue Reading about Crime watch: Charolais bull missing in Luling

Footer

Who We Are

Why Join
Leadership
Staff
Partners
FAQs
Newsroom
Sponsorships
Employment

What We Do

Theft and Law
Issues and Policy
Education
Students and Young Professionals
The Cattleman Magazine
Cattle Raisers Insurance
Cattle Raisers Trading Co.
Texas and Southwestern Cattle Raisers Association

Information

Cattle Raisers Blog
News Releases
Bereavements
Events
Sponsorships & Advertisement
Tip Hotline
Get Involved
Links

Membership

Membership Center
Membership Center Instructions
Join
Renew
  • Email
  • Facebook
  • Instagram
  • Twitter
  • YouTube

PO BOX 101988
FORT WORTH, TX 76185

1-800-242-7820

© 2023 Texas & Southwestern Cattle Raisers Association; All Rights Reserved.

COPYRIGHT | PRIVACY POLICY | TERMS OF USE