Implants: Your Common Questions Answered

Producers must be prepared to talk about value and safety of products

Growth implants have been used in the beef cattle industry for more than 50 years. Over the years, the technologies have improved and beef producers are comfortable talking about the value of implants — helping improve the productivity, feed efficiency, average daily gain and beef carcass quality.

But conversations are changing beyond talking just benefits. Consumers, and even producers, are asking more. They are asking what impact these tools have on the safety of food, the environment and animals.

“Beef producers work hard every day raising healthy and safe beef, so it’s important for them to be armed with all of the facts in exactly how they are doing this,” said Gary Sides, PhD, managing nutritionist, Beef Strategic Technical Services at Zoetis. “If producers can’t explain the value and safety of all of their management practices, then we know for sure consumers won’t be able to understand this.”

Dr. Sides recommends producers take time to review information about practices and technologies to help them feel confident communicating about the health and safety of beef they are producing. To start, here are a few questions and answers to help with some tough conversations about the use of implant technologies.

Why are implants considered safe for consumers?
The Food and Drug Administration (FDA) and U.S. Department of Agriculture have checks and balances in place to help ensure the food supply is free from unsafe levels of hormones.
• Food safety:  These products must be approved by the FDA, and approval is granted only after rigorous and extensive scientific tests to show efficacy and safety. They must be proven safe for animals, the environment and people. Producers and veterinarians also are legally and ethically obligated to follow FDA requirements for safe and effective use on farm.
• Safe hormone levels:  Throughout their history of use, these products have no documented negative effects on human health. The FDA established safe limits for hormones in meat, based on extensive scientific study and review. Hormones naturally occur in all humans, plants and animals, which includes cattle, raised organically or traditionally. This means there is no such thing as “hormone-free” beef. Consider this: A 3-ounce serving of beef from a nonimplanted steer contains 1.3 nanograms of estrogen. A 3-ounce serving of beef from an implanted steer will have just 1.9 nanograms of estrogen. One pound of implanted beef has 15,000 times less estrogen when compared with the amount of estrogen produced every day by the average adult man and nine million times less than the amount produced by a pregnant woman.1

Why are implants considered safe for the environment?
For approval and licensing, implant products need to show no significant impact on the human environment.

• Environmental assessment (EA):  In order for Zoetis to be granted approval for SYNOVEX® ONE implants, Zoetis was required by the FDA’s Center for Veterinary Medicine to show no significant effects of the active ingredients in SYNOVEX CHOICE — trenbolone acetate and estradiol benzoate — on aquatic organisms in the water systems where cattle may be fed (either pasture or feedlot locations). In 2014, after five years of research, the FDA issued a Finding of No Significant Impact, based on the results discovered in this environmental evaluation. In this EA, no significant impacts of these implants and their metabolites on humans or the environment were found in all five regions included in the study, which included waterways, air, plants or aquatic species, when these products are used according label directions.2
• Fewer emissions: Studies show animals with implants grow faster, thus having less impact on the environment than animals without implants — using less nitrogen and producing less carbon dioxide and methane per pound of protein.3 Implants help the animal retain more nitrogen, so less nitrogen is lost to the atmosphere and soil. And because producers are raising animals using less feed over a shorter time, this means less methane and manure are produced.4

Why are the use of implants valuable for the future?
To help answer this question, let’s quantify the impact of withdrawing these technologies. For example, to produce the same total amount of U.S. beef without using growth implants, U.S. beef producers would need 10 million more beef cattle, 81 million more tons of feed, 17 million more acres of land and 138 billion more gallons of water.5 The proper use of implant technologies allow beef producers to provide a safe, high-quality product for a growing population, with no significant impact on food safety and supply and the environment.

For more answers to questions about technologies that contribute to healthy and safe beef production, visit the Sustainable Beef Resource Center website at To learn more about the line of SYNOVEX implants, contact your nutritionist and local veterinarian or Zoetis representative, or visit

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

About Zoetis
Zoetis (zô-EH-tis) is the leading animal health company, dedicated to supporting its customers and their businesses. Building on more than 60 years of experience in animal health, Zoetis discovers, develops, manufactures and markets veterinary vaccines and medicines, complemented by diagnostic products and genetic tests and supported by a range of services. Zoetis serves veterinarians, livestock producers and people who raise and care for farm and companion animals with sales of its products in more than 100 countries. In 2015, the company generated annual revenue of $4.8 billion with approximately 9,000 employees. For more information, visit

For more information, contact
Leona Ling Ferguson 

Aimee Robinson
Bader Rutter


1 North American Meat Institute. Growth promotants in meat production: their use and safety. Accessed June 15, 2016.
2 U.S. Food and Drug Administration. Finding of No Significant Impact in support of a supplemental NADA 141-043. June 29, 2014.
3 Data on file, Study Report No. 0738-B-US-1-98, Zoetis Inc.
4 Neumeier C.J, Mitloehner F.M. Cattle biotechnologies reduce environmental impact and help feed a growing planet. Accessed Aug. 8, 2016.
5 Capper J, Hayes D. The environmental and economic impact of removing growth-enhancing technologies from U.S. beef production. J Anim Sci. 2012;90(10):3527-3537.



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