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SYNOVEX CHOICE® helps increase gain in feedlot steers and improve gain and feed efficiency in feedlot heifers.


SYNOVEX CHOICE® is approved for use in feedlot steers and feedlot heifers, so the same implant will help optimize performance in the feedlot and improve closeouts.1,* It helps increase average daily gain and improve feed efficiency in heifers and helps boost weight gain in steers.

SYNOVEX CHOICE provides a solid balance of performance in the feedlot and on the rail. In addition, SYNOVEX CHOICE:

  • Outperforms other implants1,2
  • Is flexible — the same implant can be used in both feedlot steers and heifers
  • Is convenient
  • - It does not require refrigeration before use.
  • - Like all SYNOVEX implants, it is administered with the SX10 Precision Applicator with its one-of-a-kind retractable needle for consistent, accurate placement.
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  • SYNOVEX CHOICE® gives steers and heifers an extra boost during their time at the feedlot because of its 10:1 ratio of trenbolone acetate (TBA) to estradiol-17B (E2).

    A formulation tailored to feedlot steers and heifers

    • Contains a 10:1 ratio of trenbolone acetate (TBA) to estradiol-17B (E2)1
    • Works as a growth-promoting implant for feedlot steers and heifers

    For more than 12 years, feedlots have counted on SYNOVEX CHOICE® for steers — and they can count on it for heifers, too.

    Outperforms nonimplanted cattle and other implants1,2

    • Compared with nonimplanted cattle and less potent (5:1 TBA:E2) implants:1

    • Compared with TBA and EB implants:2

    Click to enlarge

    A flexible and convenient implant

    • Can be used in steers or heifers, and in calf-fed cattle or yearlings
    • Administered with the SX10 applicator — like all SYNOVEX® implants — featuring an exclusive retractable needle for consistent, accurate placement
    • Store at room temperature until the package is opened, after which it must be refrigerated
    • Sold in packages of 100 implants (10 cartridges containing 10 implants each)

    Part of a broad portfolio of implants for every production stage

    • SYNOVEX C — An implant for suckling calves 45 days or older, up to 400 lb.
    • SYNOVEX S — An implant for steers weighing more than 400 lb.
    • SYNOVEX H — An implant for heifers weighing 400 lb. or more
    • SYNOVEX PLUS® — The most potent implant available for feedlot steers and heifers

    Backed by the service and support you trust from Zoetis:

    • The Implant Quality (IQ) program includes training and tools to maximize implant investment
    • The Zoetis Technical Services Team includes beef cattle nutritionists, veterinarians and meat scientists
    • Your local Zoetis representative can help determine how to incorporate SYNOVEX CHOICE into a feedlot’s implant program

    Environmental Stewardship

    SYNOVEX CHOICE is the first beef-cattle implant to meet the higher environmental impact requirements recently imposed by the Food and Drug Administration for new implants and label claims. Through research and in-depth environmental modeling, Zoetis examined exposure to and the direct impact of trenbolone acetate (TBA), estradiol benzoate (EB) and their metabolites. After the Center for Veterinary Medicine (CVM) reviewed results for those studies, Zoetis was issued a Finding of No Significant Impact (FONSI) letter for the environmental assessment regulatory submission required for licensing. This submission included evaluations in waterways, air, plants and aquatic species.

    Click here to learn more about how SYNOVEX CHOICE can help steers and heifers finish stronger.

    All SYNOVEX formulations are compatible with both the SX10 and Revolver applicators

  • SYNOVEX CHOICE® is easy to administer with the SX10 applicator, which features a one-of-a-kind retractable needle for consistent, accurate placement of the implant.The SX10 applicator can be used to administer all SYNOVEX ® implant formulations so processing is simplified because it only takes one gun chuteside.

    To administer SYNOVEX CHOICE with the SX10 applicator, follow the instructions included with the applicator for loading the implant clip, cocking the applicator, disinfecting and cleaning, replacing the needle, and removing the implant clip.

    English and Spanish training videos are conveniently available online to help educate feedlot employees on implanting techniques, sanitation and use of the SX10 applicator.

    All SYNOVEX formulations are compatible with both the SX10 Precision Applicator and metal revolver applicators.

  • The Implant Quality (IQ) program from Zoetis helps you get the most out of your SYNOVEX CHOICE® implant. It provides:

    • Establishment of implanting goals
    • Development of a customized quality assurance (QA) program to fit the operation’s goals
    • Training of crew members in correct sanitation and implanting techniques
    • Monitoring and analysis of results

    The program includes several useful tools:

    • Sanitation gear, including a disinfecting tray, sponge and ear brush, to help clean the ear prior to implanting
    • Service reports to assess implanting techniques of the processing crew and to check animals for implant retention three to four weeks later (available in paper or electronic formats)
    • Certificates of completion for all members of the processing crew

    Ask your local Zoetis representative how to get started with the IQ program.

  • *Based on average daily gain and feed efficiency demonstrated in the Herschler study referenced below and May 30, 2014, CattleFax market and feed prices.

    1 Herschler RC, Olmstead AW, Edwards AJ, et al. Production Responses to Variable Doses and Ratios of Estradiol Benzoate and Trenbolone Acetate Implants in Steers and Heifers. J Anim Sci. 1995;73(10):2873-2881.

    2 Cleale RM, Amodie D, Bechtol DT, et al. Effects of estradiol benzoate and trenbolone acetate, alone or in combination at dose levels present in Synovex Choice, on performance by feedlot heifers. J Anim Sci. 2013;91(2):970-977.

    3 U.S. Food and Drug Administration. Finding of No Significant Impact in support of a supplemental NADA 141-043. June 29, 2014.

IMPORTANT SAFETY INFORMATION: Do not use SYNOVEX products in veal calves. Refer to label for complete directions for use, precautions, and warnings.



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