The pigs and poultry in Professor Xingen Lei's lab have been consuming feed one wouldn't expect in Ithaca: marine algae.

The Cornell animal science professor is testing the unlikely material as a new protein-rich source of feed to supplement and replace some of the corn and soybean meal mix traditionally given to food-producing animals.

By doing so, he could transform a biofuel byproduct into a valuable commodity, potentially freeing thousands of acres of cropland.

"Current animal feed directly competes against human food sources and, thus, is unsustainable," Lei said. "We must develop alternatives to soybean and corn for animal feeds."

Algae produces 50 times more oil per acre than corn, with a much smaller carbon footprint; uses nutrients more efficiently than land plants, with no runoff; and places no demand on high-quality agricultural land or freshwater supplies.

There are an estimated 1 billion swine, 1 billion cattle, 2 billion sheep and goats and 40 billion poultry worldwide. The average pig consumes about 660 pounds of feed by the time it goes to market, Lei said, so replacing just 10 percent of that feed with algae would save a whopping 33 million tons.

Lei's preliminary research found that dried defatted algae derived from biofuel production can replace up to one-third of soybean meal in diets for pigs and chickens. It is an attractive source because it is high in protein -- 20-70 percent, compared with about 10 percent in corn and 40 percent in soy.

Lei and his researchers are now working to determine which algae are best, and the proper ratios of algae, soybean and corn. They are also discerning whether there are risks or additional health benefits for humans in resultant products, such as meat and eggs.

The samples are shipped to his lab from Hawaii, where algae is being cultivated on a few acres near the Kailua Kona Airport as part of a $15 million pilot project by Cellana and a multi-university consortium led by Cornell professors Chuck Greene, professor of earth and atmospheric sciences, and Jeff Tester, professor of chemical and biomolecular engineering.