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  5. FDA Provides a List of the Currently-Approved and Currently-Marketed Implants Available by Beef Cattle Target Animal Class Which Clarifies the Approved Conditions of Use Regarding Use in a Reimplantation Program
  1. Product Safety Information

FDA Provides a List of the Currently-Approved and Currently-Marketed Implants Available by Beef Cattle Target Animal Class Which Clarifies the Approved Conditions of Use Regarding Use in a Reimplantation Program

On December 10, 2021, the FDA issued an update announcing the target date of July 1, 2023, for the sponsors of beef cattle ear implants to update the labeling of their products regarding reimplantation within a production phase. FDA also provided additional information and a list of frequently asked questions on May 12, 2023, to clarify the beef cattle target animal classes described in Appendix III of Guidance for Industry (GFI) #191, how CVM interprets beef cattle production phases, and the implications for use of beef cattle ear implants after July 1, 2023.

This website is intended to be an additional resource for beef cattle producers to easily determine which implants are approved for use in each production phase and if the cattle ear implant product they wish to use is approved for use in a reimplantation program, in which more than one implant is administered to an animal in a single production phase. This website will be updated as new or supplemental beef cattle ear implant approvals occur. 

The following tables provide a list of the currently-approved and currently-marketed implants available by beef cattle target animal class (i.e., production phase). The tables use the terminology on the product labeling and from Appendix III of GFI #191. The cattle target animal class definitions are based on differences in physiological state and management of the animals at each phase and are reflective of the conditions of use that were used in regulatory studies to demonstrate safety and effectiveness of the product for FDA approval. FDA acknowledges that beef cattle production industry nomenclature and terminology differs across the United States, and the terminology used by FDA for regulatory purposes does not always align perfectly with those terms. However, this does not permit creative interpretation of the cattle production phases for which implants are approved. 

On or before June 30, 2023, the labeling of all beef cattle ear implants was updated regarding reimplantation within a production phase. However, as product with updated labeling enters distribution channels, products with older labeling may be commercially available as inventories of such product are depleted. Unless the labeling of a cattle ear implant clearly states that it is approved for reimplantation within a production phase, it is not approved for reimplantation. The tables below clarify the approved conditions of use.

All beef cattle ear implants listed in the tables are available commercially over-the-counter, except those products denoted with a double-dagger (‡), which are only to be used by or on the order of a licensed veterinarian. Prescription marketing of beef cattle ear implants does not, however, allow for extralabel use by veterinarians or non-veterinarians.

Some of the implants listed below include a “duration of effectiveness” statement, such as “up to 200 days”. This is included for extended-release implants that have a longer payout period compared to “traditional” implants. This duration is not meant to imply that animals held after the end of the duration period are misbranded or adulterated. Rather, it reflects the conditions of use in the regulatory studies used to support FDA approval. A producer using an implant for “increased rate of weight gain for up to 200 days” can expect animals receiving an implant to gain faster compared to non-implanted animals for up to 200 days after implantation. After 200 days, the effectiveness of the implant was not evaluated and is not known.

Beef Calves

Implant Name Indications for Use Approved for Reimplantation in this Class
Component E-C
(progesterone and estradiol benzoate implants)
For increased rate of weight gain in beef calves 45 days of age or older and weighing up to 400 pounds No
Component E-C w/ Tylan
(progesterone and estradiol benzoate and tylosin tartrate implants)
For increased rate of weight gain in beef calves 45 days of age or older and weighing up to 400 pounds No
Compudose
(estradiol extended-release implants)
For increased rate of weight gain for up to 200 days in beef steer calves 2 months of age and older No
Encore
(estradiol extended-release implants)
For increased rate of weight gain for up to 400 days in beef steer calves 2 months of age and older No
Ralgro
(zeranol implants)
For increased rate of weight gain in beef calves 2 months of age or older No
Synovex C
(progesterone and estradiol benzoate implants)
For increased rate of weight gain in beef calves 45 days of age and older and weighing up to 400 lbs No

Growing Beef Cattle on Pasture (Stocker, Feeder, and Slaughter)

Implant Name Indications for Use Approved for Reimplantation in this Class
Component TE-G
(trenbolone acetate and estradiol implants)
For increased rate of weight gain in growing beef steers and heifers on pasture (stocker, feeder, and slaughter) No
Component TE-G w/ Tylan
(trenbolone acetate and estradiol and tylosin tartrate implants)
For increased rate of weight gain in growing beef steers and heifers on pasture (stocker, feeder, and slaughter) No
Compudose
(estradiol extended-release implants)
For increased rate of weight gain for up to 200 days in growing beef steers on pasture (stocker, feeder, and slaughter) No
Encore
(estradiol extended-release implants)
For increased rate of weight gain for up to 400 days in growing beef steers on pasture (stocker, feeder, and slaughter) No
Ralgro
(zeranol implants)
For increased rate of weight gain in growing beef steers and heifers on pasture (stocker, feeder, and slaughter) No
Revalor-G
(trenbolone acetate and estradiol implants)
For increased rate of weight gain in growing beef steers and heifers on pasture (stocker, feeder, and slaughter) No
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 on pasture (stocker, feeder, and slaughter) No

Growing Beef Cattle in a Dry Lot

Implant Name Indications for Use Approved for Reimplantation in this Class
Ralgro
(zeranol implants)
For increased rate of weight gain in growing beef steers and heifers in a dry lot No
Synovex Choice (trenbolone acetate and estradiol benzoate implants) For increased rate of weight gain in growing beef steers and heifers in a dry lot No
Synovex Primer (trenbolone acetate and estradiol benzoate implants) For increased rate of weight gain in growing beef steers and heifers in a dry lot No

Growing Beef Cattle Fed in Confinement for Slaughter

Implant Name Indications for Use Approved for Reimplantation 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 slaughter No
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 slaughter No
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 slaughter No
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 slaughter No
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 slaughter No
Ralgro
(zeranol implants)
For increased rate of weight gain and improved feed efficiency in growing beef steers and heifers fed in confinement for slaughter No
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 slaughter No
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 slaughter No
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 slaughter No
Revalor-IH
(trenbolone acetate and estradiol implants)
For increased rate of weight gain in growing beef heifers fed in confinement for slaughter No
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 slaughter No
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 slaughter No
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 slaughter No
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 slaughter Yes

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 slaughter No
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 slaughter No
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 slaughter Yes

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 slaughter Yes

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.

 

 
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