I HAVE made many presentations over the last year for the National Pork Producers Council, the National Pork Board, the Iowa Pork Congress and the Minnesota Pork Congress, to name a few.
The talks have centered on the use of antibiotics in animals raised for food and what relationship, if any, that practice may have in causing antibiotic resistance in human pathogens.
I have met many people and heard many stories about hog production practices. One of the more interesting stories I heard along the way was about a new Food & Drug Administration-approved veterinary prescription product that is a safe alternative to physical castration of young male piglets.
Prior to delving more into this issue, I had always assumed that pigs were castrated because boar meat would be tough and stringy. Instead, I have learned that castration is done to prevent an unpleasant phenomena encountered when cooking boar meat called "boar taint," or off-odors. Off-odors make for very unpleasant cooking and dining experiences.
Not to get too technical, but boar taint is caused by two chemicals that get stored in the pig's fat: androstenone, which is produced by the testicles once the pig reaches puberty, and skatole, which is produced in the intestines and cannot be broken down by the liver if testosterone is being produced. Surgical castration greatly reduces these compounds because there are no end organs to respond to the hypothalamus-pituitary-gonad endocrine axis.
Improvest produces the same results, but only temporarily, and along the pig's life, there are some positive changes, such as a 6-10% improvement in feed efficiency and a 4.2% improvement in average daily gain. The risk of infection or death is decreased by 1.6% in pigs that are immunologically castrated by Improvest versus physically castrated. The bottom line is that there is a 2.0-2.5% increase in cutout yield.
Add to that the positive environmental impact and the improvement in pig health and well-being, and it is no wonder that the global brand, called Improvac, has been used for more than 10 years in many countries.
I am hoping to learn, either from responses to this column or in future discussions, why the product has been so slow to catch on in the U.S.
Here's how the technology works. As male pigs mature, the hypothalamus sends a message to the pituitary gland, which is the gland that controls most of the endocrine system. The messenger is called gonadotropin releasing factor (GnRF). GnRF stimulates the pituitary to send out leutinizing hormone and follicular stimulating hormone to the testicles, activating them, so to speak, to produce testosterone and androstenone.
Improvest is a subcutaneous injection that's given twice in a pig's lifetime. The first merely sets the stage for the second injection, which usually follows four weeks later. The second injection causes the pig to develop antibodies to GnRF, which temporarily blocks the endocrine axis for about 10 weeks. The testicles go dormant, and the risk of boar taint is greatly reduced, similar to physical castration.
The market window is 3-10 weeks after the second injection. There is no residue in the pork meat. The only concern with going to market sooner than three weeks or later than 10 weeks from the second injection is boar taint. There is no human health risk.
To repeat, this is temporary only. These young, intact male pigs will have that endocrine axis activated and, thus, will put on more weight with increased feed efficiency until the second injection. Normal activity, such as some aggression and mounting, will likely occur but will disappear by three weeks after the second injection.
Improvest itself is not a hormone, not a feed additive, not an antibiotic and not a chemical castration. It IS a temporary, immunological blockade of the endocrine axis I described.
Denmark is calling for a voluntary cessation of surgical castration of young pigs by 2018. The only alternatives I can find to avoid boar taint are going to market early, maybe some breeding and genetic stuff way down the road and Improvest.
With all the clambering in the U.S. about sow housing, pain-free castration and dehorning and blunt trauma euthanasia, accompanied by the many undercover videos of screaming piglets being held upside down, I can only guess how long it will take before this issue is addressed in a similar fashion as the Danes.
After all, we are following in their footsteps on banning antibiotics for growth promotion uses, are we not?
Note: In full disclosure: Zoetis, which has the only gonadotropin releasing factor analog (Improvest), has asked me to assist in messaging on this product and perhaps discuss it with interested parties such as producers, packers and consumer groups. I am compensated for my time. However, Zoetis did not see this column before I sent it to my editor at Feedstuffs, and it may not represent the views of Zoetis.
I also serve on the Tyson Foods Animal Well Being Advisory Panel, but we have not discussed this issue at any of our meetings, and I am not speaking for Tyson Foods or the panel.
Important worker safety information: Pregnant women should not administer Improvest. Women of childbearing age should exercise extreme caution when administering this product. Take special care to prevent accidental self-injection because of the negative effects on reproductive physiology in both men and women. However, there is no risk associated with consuming pork from animals administered this product.
*Dr. Richard Raymond is a former U.S. Department of Agriculture undersecretary for food safety.