Getting great-tasting pork to your table.

From perfectly grilled chops to sizzling bacon, we Americans love pork. And America’s pig farmers work hard every day to put sustainable, healthy and great-tasting pork on your table.

Pig Care 

Everything from the practices, technology and even the nutritional plan pig farmers use is designed to improve pig well-being and the quality of pork you buy. This includes the castration of male pigs. Until recently, it’s been the only method found to successfully reduce aggression in male pigs as well as preserve the flavor of pork and eliminate bad odors, known as boar taint. To learn more about responsible farming practices, visit PorkCares.org

Today’s Alternative

Some pig farmers have chosen to stop physical castration of male pigs and use an alternative option to achieve the same results. They use Improvest® (gonadotropin releasing factor analog-diphtheria toxoid conjugate), an approach to animal care that allows pigs to grow more naturally and cause less environmental impact compared with traditional castration.1,2 Improvest gives farmers a choice to raise pigs differently, and it benefits pigs and people who eat pork.

Raised Naturally

  • Grows naturally
  • Not an antibiotic
  • Not a hormone or growth promotant

Raised Safely

  • Works like a vaccine
  • Lowers male pig aggression3
  • Reduces animal stress4

Raised With Less Impact1

  • Lowers carbon footprint
  • Produces less manure
  • Uses less feed

Confidence in Your Pork

Pork from pigs raised with Improvest delivers the same mouthwatering flavor you love. Plus, you can be confident the pork you serve friends and family is the highest quality.

Globally Trusted

  • Approved by over 60 countries. See Map
  • Safely used globally for 10+ years6
  • 15 billion+ servings of pork raised with Improvest

Tested and Proven

  • Thoroughly tested for safety
  • FDA-approved6
  • No additives in meat

Premium Experience

  • Same great flavor
  • No unappetizing odors
  • High quality

Questions You May Have

Here are some answers to questions you may have about Improvest and boar taint.

Why do farmers castrate male pigs?

The simple answer is to ensure pork tastes great every time people eat it. Male pigs are castrated to eliminate unpleasant odors, called boar taint — caused by physiological changes that happen naturally as male pigs mature. Eating pork when boar taint is not eliminated can leave people thinking they bought a bad piece of meat. Castration prevents the odors from collecting in the meat and impacting its flavor. Additionally, castration lowers male aggression so animal well-being is improved.

How does Improvest® work?

Improvest works like a vaccine. It uses the pig’s own immune system to naturally block hormones that can cause meat to taste bad. Scientifically speaking, Improvest is a protein that creates a temporary immune response to provide the same effect as traditional castration. It is not a hormone or growth promotant, nor is it chemical castration.

Are there alternatives to castration?

Currently, Improvest is the only commercially available alternative to traditional castration and has been approved for use in more than 60 countries for over 10 years. Other alternatives include raising male pigs to lower weights (before they mature and begin to produce the bad odors), testing female-only raising practices and feeding specific nutritional programs. However, none of these completely eliminate boar taint, and many are not viable or fully tested for use in modern farming.

Is Improvest safe?

Improvest is safe. Improvest was approved for use after extensive food safety studies concluded that it contains no unsafe residues in pork that could affect human health and that meat from pigs given Improvest is safe to eat, according to the U.S. Food and Drug Administration (FDA).6 Additionally, a panel of medical professionals, including
physicians, dietitians, nutritionists and veterinarians, agreed with the FDA that pork from pigs given Improvest® is safe for people to eat.

How is Improvest given to male pigs?

Improvest is given to pigs much like vaccinations are given. Specially trained farm workers administer the two shots, an initial dose given when the pig is 9 weeks old and the second dose four weeks later.

How does Improvest improve pig care?

Many people who eat meat increasingly want to know meat-producing animals are raised humanely. Improvest helps reduce aggression in male pigs and allows pigs to grow more naturally, eliminating the need for early animal care interventions that can impact their welfare. It gives food companies another reason to be confident in the story behind the pork they sell.

How is Improvest
more environmentally sustainable?

Improvest is a great example of sustainable agriculture, helping farmers and food companies produce quality pork with less environmental impact.1 With Improvest, boars are allowed to act like boars and grow more naturally over their lifetime. If all pig farmers used Improvest, it would save the equivalent of 5 million bottles of water and reduce greenhouse gas emissions equal to removing 380,000 cars from the road.1

Learn More

Boar taint and the 
experience of pork

Professional opinions on boar taint and castration

Approval and testing of Improvest

Other countries on castration and pig care

Improving the environmental
impact of farming

Modern
pig farming

Assessing pig 
care implications

IMPORTANT SAFETY INFORMATION: Pregnant women should not administer Improvest. Women of childbearing age should exercise extreme caution when administering this product. Exercise special care to prevent accidental self-injection because of negative effects on reproductive physiology in both men and women. However, there is no risk associated with consuming pork from animals administered this product. Improvest should not be used in female pigs, barrows, or male pigs intended for breeding. For more information, please see full Prescribing Information.

Regulatory authorities in more than 60 countries, including the European Union and Japan, have reached the same conclusion for the related global brand, Improvac®.

REFERENCES 1 Data on file, Study Report No. AR-01305, Zoetis Inc.
2 Boler DD, Clark DL, Baer AA, et al. Effects of increasing lysine on further processed product characteristics from immunologically castrated male pigs. J Anim Sci. 2011:89(7):2200-2209.
3 Rydhmer L, Lundström K, Andersson K. Immunocastration reduces aggressive and sexual behaviour in male pigs. Animal. 2010;4(6):965-972. 4 Allison J, Pearce M, Brock F, Crane J. A comparison of mortality (animal withdrawal) rates in male fattening pigs reared using either physical castration or vaccination with IMPROVAC as the method to reduce boar taint, in Proceedings. 21st IPVS Congress 2010; 1139.
5 European Medicines Agency. Public Assessment Report. http://www.ema.europa.eu/docs/en_GB/document_library/EPAR_-_Scientific_Discussion/veterinary/000136/WC500064057.pdf Accessed March 9, 2018.
6 Freedom of Information Summary. NADA 141-322 - IMPROVEST Gonadotropin Releasing Factor - Diphtheria Toxoid conjugate Sterile Solution for Injection Swine, intact males. Food and Drug Administration; 2011.

Copyright ©2018 Zoetis. All rights reserved. The product information provided in this site is intended only for residents of countries in which it is approved for sale. The products discussed herein may have different label indications in different countries. The animal health information contained herein is provided for educational purposes only and is not intended to replace consultation with your veterinarian. All decisions regarding animal health care must be made with a veterinarian, considering the unique characteristics of each operation and producer's situation. IMP-00086

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