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FDA Approves New Pig Castration Option

IMPROVEST is a protein compound that uses the pig’s own immune system to provide the same effect as surgical castration, but much later in the male pig’s life

The Food and Drug Administration (FDA) has approved IMPROVEST (gonadotropin releasing factor-diptheria toxoid conjugate), an option for farmers to use for safe and effective castration and to reduce boar taint in intact male pigs intended for pork.

IMPROVEST is a protein compound that uses the pig’s own immune system to provide the same effect as surgical castration, but much later in the male pig’s life.

Without surgical castration, the animal grows with all the inherent advantages of intact males until the second dose of the product. Studies confirm that intact male pigs eat less feed and produce more meat, increasing feed efficiency by 6 to 10%. Cutout yields typically improve by 2 to 2.5%. Since male pigs given IMPROVEST are not surgically castrated, the risk of infection or death is eliminated, decreasing mortality by 1.6%.

Producing pork more efficiently potentially reduces the carbon footprint by as much as 3.6% (measured in CO2 equivalent per kilogram of pig live weight) vs. barrows.

“IMPROVEST creates an opportunity to capture more value from male pigs that didn’t exist until now,” says Jim Bradford, DVM, director, Team Lead, IMPROVEST, Pfizer Animal Health. “Male pigs are given IMPROVEST later in the finishing phase to manage boar taint, so they’re able to grow to their full intact male potential, and do it more efficiently.”

This technology is approved in 58 other countries around the world under the related global brand, IMPROVAC.

Pigs are injected with IMPROVEST. The first dose primes the system and should be administered no earlier than nine weeks of age. The second dose should be given at least four weeks after the priming dose.

Pigs should be marketed no earlier than four weeks after the second dose of the product to allow adequate time for reduction in the compounds responsible for off odor in pork. Marketing pigs on the IMPROVEST program more than eight weeks after the second dose may increase the risk of off odor in pork.

Only trained, certified technicians will be permitted to administer the product as part of the quality assurance program.

As the product is gradually introduced, Pfizer Animal Health will work with veterinarians and their producer clients to help them adopt new nutritional guidelines and best handling practices to optimize growth for intact males.

“This gradual approach provides the time needed to ensure a coordinated food chain effort, and gives processors and packers time to integrate and optimize this into their systems as well,” Bradford says. “We want to ensure the best IMPROVEST program experience for everyone – from farmers to meat packers, processors and retailers, and, ultimately, to consumers.”

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TAGS: Nutrition