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Helps increase gain and improve feed efficiency in stocker and feedlot steers.


Administering SYNOVEX® S to stocker or feedlot steers can help boost gain, enhance feed efficiency and deliver exceptional return on investment. Steers implanted with SYNOVEX S:

  • Gained an additional 25 pounds on pasture over nonimplanted animals1
  • Delivered a 20:1 return on investment under most cattle pricing situations*,2
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  • A formulation tailored to stocker and feedlot steers

    • Contains 200 mg of progesterone and 20 mg of estradiol benzoate
    • Works as a growth-promoting implant for stocker and feedlot steers

    A flexible and convenient implant

    • Administered with the SX10 Precision Applicator — like all SYNOVEX® implants — featuring an exclusive retractable needle for consistent, accurate placement
    • Can be stored at room temperature until the package is opened

    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 H — An implant for heifers weighing 400 lb. or more
    • SYNOVEX CHOICE® — An implant for feedlot steers and heifers
    • 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 S into your stocker or feedlot operation

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

  • SYNOVEX® S is approved for:

    • Increased rate of weight gain and improved feed efficiency in stocker and feedlot steers weighing more than 400 lb.
    • For additional improvement in rate of weight gain in steers fed in confinement for slaughter, re-implant at approximately 70 days.

    One implant (eight pellets) is administered to each steer by subcutaneous implantation in the middle one third of the ear.

    Do not use in veal calves.

  • SYNOVEX® S 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 S 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® S 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 Herschler study referenced below and May 30, 2014, CattleFax market and feed prices

    1 Data on file, 159-trial summary evaluating SYNOVEX use in more than 24,000 head of grazing cattle, Zoetis Inc.

    2 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.

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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