WASHINGTON – An expert who testified on July 14 at a congressional hearing on antibiotic use in livestock production and antibiotic resistance in humans argued that “All uses of antibiotics improve animal health, and these improvements in animal health can substantially improve human health.”

According to the National Pork Producers Council (N.P.P.C.), Randal Singer, associate professor of epidemiology at the University of Minnesota, who for 12 years has studied antibiotic uses and antibiotic resistance, told the House Energy and Commerce Subcommittee on Health what the N.P.P.C. and other livestock groups repeatedly have stated about antibiotic use in food-animal production: “The best way to manage antibiotic uses in animal agriculture is through sound, rational, science-based policy.”

Modern livestock production opponents, however, argue that antibiotic use in food animals is leading to an increase in antibiotic resistance in humans and, therefore, antibiotic use in livestock production must be restricted. Several groups are supporting legislation sponsored by Rep. Louise Slaughter, D-N.Y., and the late-Sen. Edward Kennedy, D-Mass., that would ban the use in livestock and poultry of antibiotics that prevent or control diseases and improve feed efficiency and weight gain, according to N.P.P.C.

Congressional hearing witnesses, testifying in favor of such a ban, claimed that a number of studies link use of antibiotics in livestock with antibiotic resistance in humans, and they cited the results of a 1998 ban in Denmark on antibiotic growth promoters and preventatives.

Mr. Singer countered, “the removal of growth-promoting antibiotics from use in food animals in Denmark resulted in an increased reliance on therapeutic doses of medically important antibiotics to treat the ill animals.” Top scientists for the Centers for Disease Control and Prevention and the National Institutes of Health testified in April there is no scientific study linking antibiotic use in food-animal production with antibiotic resistance in humans.

“Pork producers have a moral obligation to use antibiotics responsibly, under the direction of a veterinarian, to protect public health and produce safe food,” said Howard Hill, D.V.M., a member of the N.P.P.C. board of directors. “Producers also have an ethical obligation to maintain the health of their pigs, and antibiotics are an important tool to help us do that.”