NASHVILLE - Many cooks in Tennessee are planning "sustainable" Thanksgiving meals this year with naturally raised turkeys.

That's because leading medical groups have been expressing concern that the overuse of antibiotics in animal production is creating new strains of bacteria difficult to treat in people.

Robert Martin, senior officer with the Pew Environment Group, directed a two-and-a-half year study on farm animal production.

"Our number one public health recommendation was to eliminate the non-therapeutic use of antibiotics in food animal production."

Martin says at least 70 percent of the antibiotics purchased in the United States are used on healthy animals to prevent illness due to overcrowding and poor waste management.

Some meat industry experts argue that there is not enough evidence that antibiotics in animals cause health problems in humans. Still, many people choose to buy only free-range antibiotic-free turkeys for their Thanksgiving dinner.

Martin says free-range, natural turkeys are more nutritious, even though they look a little different.

"They will look different. They'll look leaner but will also taste better."

A list of Tennessee organic farms offering antibiotic- and hormone-free meats, including turkey, is available at http://www.eatwild.com/products/massachusetts.html.