JMAFF Approves Pfizer Animal Health’s IMPROVAC as Safe and Effective for Pigs in Japan

Pfizer to Expand Veterinary Experience Before Launch Later this Year

TOKYO, Japan – February 8, 2010 –.Pfizer Animal Health today announced it will begin to expand Japanese veterinary experience with IMPROVAC, Pfizer’s successful pork production technology embraced by pig farmers in other countries for more than 10 years. The Japanese Ministry of Agriculture Forestry and Fishery (JMAFF) has approved IMPROVAC as safe and effective for use by veterinarians in pigs throughout Japan.

"In the months ahead, the experience gained with IMPROVAC by a group of veterinarians and swine producers will enable Pfizer to support veterinarians throughout the country more effectively when IMPROVAC becomes more widely available for prescription in late 2010,” said Yukihiro Takemoto, Livestock Business Unit Director, Pfizer Animal Health, Japan.

Pfizer plans to train and assist veterinarians and their pork producer clients on the proper use of IMPROVAC to help them maximize the value that it can deliver to their operations.


IMPROVAC uses the pig’s own immune system to temporarily interrupt testicular function, which results in the control of the level of key “boar taint” causing compounds at the time of the slaughter. Up to now the only way to reduce boar taint has been to physically castrate male piglets early in life or to slaughter them young, before the risk of taint is high.

IMPROVAC is administered as two doses: the first ‘primes’ the immune system and the second (at least 4 weeks later) stimulates the production of antibodies to control boar taint.

IMPROVAC allows male pigs to maintain their natural male growth patterns up to the time of the second injection, resulting in a more efficient feed conversion and producing the same quality meat of physical castrate pigs. IMPROVAC also improves the welfare of pigs by avoiding the stress, pain, and mortality associated with the physical castration of piglets. Furthermore, physical castration changes the natural growth patterns of boars, so they convert feed less efficiently and produce fatter carcasses.

Pork products from pigs who have received IMPROVAC have been proven to be safe to eat and have been enjoyed by millions of pork consumers in many countries of the world. IMPROVAC is now approved for use in 55 countries, including Japan.

About Pfizer Animal Health

Pfizer Animal Health, a business of Pfizer Inc., is a world leader in discovering and developing innovative animal prescription medicines and vaccines, investing an estimated $300 million in R&D annually. For more information on how Pfizer works to ensure a safe, sustainable global food supply with healthy livestock and poultry, or how Pfizer helps companion animals and horses to live longer, healthier lives, visit

For more information contact:

 Miho Kawashima  Rick Goulart
 Pfizer Corporate Communications  Pfizer Animal Health Media Relations
 Japan +81 3 5309 7057  US 212.733.7457





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