Dieting to lose weight and improve your health?
Millions of chickens in Delaware--one of the nation's top poultry producers--have been on a diet to reduce their impact on the environment and improve the health of the state's waterways, and it appears to be working.
Extensive research led by William Saylor, professor of animal and food sciences at the University of Delaware, has confirmed that Delaware chickens now digest more of the phosphorus, an essential nutrient, in their feed, thanks to the addition of a natural enzyme called phytase. As a result, about 23 percent less phosphorus is output in chicken manure.
So now when poultry litter is used to fertilize a farm field, a lot less phosphorus is available to potentially leach from the soil or be carried off in storm water to a river or bay.
And that's good news for waterways like Delaware's Inland Bays, where overloads of nutrients, particularly phosphorus and nitrogen, have contributed to serious water-quality problems, such as massive blooms of algae and fish kills.
To put it in perspective, in 2006, Delaware farmers produced over 269 million broiler chickens--1.8 billion pounds of poultry--valued at more than $739 million, according to the Delmarva Poultry Industry. Those chickens produced more than 280,000 tons of waste.
According to recent analyses by David Hansen, UD assistant professor of soil and environmental quality, there are now about 19 pounds of phosphorus in a ton of Delaware poultry litter compared to 25 to 30 pounds of phosphorus per ton of litter just five years ago. The 30-40 percent reduction is credited to phytase-modified diets and other nutrient management practices adopted by poultry farmers under Delaware's Nutrient Management Law of 1999. That reduction means that the phosphorus load to the environment has been reduced by some 2 million to 3 million pounds per year.
Addressing a weighty problem
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Contact: Tracey Bryant
tbryant@udel.edu
302-831-8185
University of Delaware
31-Jul-2007