The U.S. government has granted Texas A&M University $18 million to find ways to prevent terrorists from attacking the nation's food supply and possibly human health by spreading diseases through livestock. No one is certain how real the threat might be, but experts say the cost of not being prepared could be enormous.

While most anti-terrorism efforts concern possible direct threats to humans from such things as bombs, radiation or biological agents, the federal grant to Texas A&M involves biological warfare aimed at cows, pigs, chickens, and other sources of animal protein. A successful introduction of a disease in U.S. livestock could imperil the nation's food supply. Experts say there could also be diseases introduced to animals that could then spread to humans.

Texas A&M researcher Neville Clarke, who worked on the grant proposal, says of the 60,000 scientists in the old Soviet Union who were involved in bio-weapons research about 10,000 were focused on developing diseases that attack plants and animals. He says the threat may not have disappeared with the collapse of the communist government.

"We know that that technology has been developed and there has been a good deal of thinking about it, and that perhaps some of the materials or even some of the scientists who were involved with that could be working for other folks now," said Mr. Clarke.

One way of approaching the problem of bio-terror aimed at livestock is to refine methods currently in use to deal with accidental outbreaks of disease in animals. Generally, accidental outbreaks occur at one place and can be isolated, as was done recently with the avian influenza in Southeast Texas. But Mr. Clarke says terrorists could be expected to make things more complicated.

"The more likely scenario, if someone is going to do this intentionally, would be to introduce it at multiple sites," he said. "So you have the increase in the amount of resource that it takes to respond and the complexity of trying to deal with multiple responses."

One disease that has researchers worried is hoof-and-mouth disease, which is caused by a virus and is highly contagious among cattle, sheep, hogs and other cloven-hoofed animals. Two years ago, officials in Britain ordered the slaughter of almost 2.5 million animals to stop an outbreak of the disease.

Under the federal grant, Texas A&M will work during the next three years with research partners in four other U.S. universities to develop defense strategies against such diseases. At the same time, a $15 million federal grant will help scientists at the University of Minnesota work on plans to protect the nation's overall food supply. Officials from the Department of Homeland Security will work closely with both universities to develop their plans.