23 November 1999
A Vitamin Boost for Thanksgiving
by Kate Melville
In America, Thanksgiving and Christmas dinner wouldn't be complete without turkey on the menu. So given the size of the US population (not to mention their appetites) producing enough birds can be a national obsession (between 300 million and 360 million young poults are consumed each year). But thankfully new research by North Carolina State University scientists will help ensure there will always have a plentiful supply.
The researchers found that adding a tiny amount of iodine to a female turkey's feed can boost the number of eggs that hatch successfully, and also promote healthier, faster growing young birds.
"This is natural growth, not synthetically induced or genetically engineered," said led by Dr. Vern Christensen, professor of poultry science. "Iodine is a naturally occurring component of thyroid hormones. We've found that it plays a key role in helping organ systems mature faster than they would have normally, so a young poult's state of maturity at hatching is more advanced."
Christensen's team produced a 4.2 percent increase in hatching rates and a 50 percent improvement in post-hatching survival rates plus significantly faster growth just by adding just four parts per million of iodine to breeder hens' feed.
Most other research in this area has focused on devising ways to boost the growth of muscle mass, often to the detriment of the embryos' other developing organ systems. "When a turkey is genetically selected for increased muscle mass development, there's often a trade-off, because it gives up growth in other vital organ systems, like the heart or lungs," Christensen says. This means that although the embryo has the muscles to break through the shell, its life-sustaining organs are less mature than they should be, making it more likely to die or grow more slowly.
The physical cost of feeding breeder hens an iodine-enriched diet is negligible, just a few cents per ton of feed. Yet the financial payoff may be substantial. However given the heat in the genetic food debate in Europe don't look for this trend to catch on outside the America any time soon!