February 1, 2008 Poultry nutritionists add an enzyme called phytase to chicken feed in an effort to decrease the amount of phosphorus that passes through them undigested. Research revealed the maximum amount of phytase that can be added to the feed without harming the health of the chicken. Reducing the amount of phosphorus that passes into chicken waste also reduces the phosphorus runoff into rivers and bays that can cause algal blooms and fish kills.
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Millions of chickens, like many Americans, are starting a new diet regimen, but instead of helping to lose weight, the diet helps the environment.
Millions of chickens eat a lot, and excrete a lot of waste -- which can get into soil and can get carried off in storm water waterways. Now, poultry nutritionists are watching what chickens eat to help keep chemicals out of the environment.
"What we're doing is to make changes that will enable the bird to grow well, to be healthy and still have a reduction on the environmental imprint," William Saylor, Ph.D., Nutritionist at the University of Delaware, told Ivanhoe.
Chicken feed contains an essential nutrient called phosphorus -- but chickens bodies can't absorb it, so any excess passes thru the bird -- polluting the environment. Adding an enzyme called phytase to chicken feed helps birds digest more phosphorus.
Inside the birds digestive track, the phytase enzyme breaks down phosphorus molecules, so that the bird can absorb and utilize more of it … and less goes to waste.
"We've found reductions in phosphorus excretions from 25 to as much as 50 or 60 percent," Dr. Saylor said.h A big impact worth crowing about.
When is phosphorus bad for the environment? Phosphorus is one of the six most used chemicals in nature, so it's not all bad. But when too much phosphorus gets into a body of water, it can stimulate the growth of algae -- so much that the algae cover the water in a sheet that blocks out sunlight. Plants can't grow under this "red tide" of algae, so they die.
Bacteria eat the plants, and use up all the oxygen in the water. That's bad news for the fish, shrimp and crabs, or anything else that lives in the water. Red tides aren't always red—they can be green, too. Too much nitrogen can also cause a sheet of algae to grow out of control. Phosphorus and nitrogen are common ingredients in fertilizers as well as feed.
The American Geophysical Union and the American Waterworks Association contributed to the information contained in the video portion of this report.

