Ms. Winfrey has been swamped with requests for tickets to her tapings here. The president of the local Chamber of Commerce initially forbade chamber employees to attend, explaining that Amarillo stood by its beef producers and adding that ''we are not going to have any red-carpet rollouts, key to the city, flowers'' for Ms. Winfrey. But he quickly rescinded his order, especially after the president of the local chapter of the National Association for the Advancement of Colored People said he was ''dismayed, shocked and mystified'' by it.

Ms. Winfrey clearly has many supporters here -- as she entered the J. Marvin Jones Federal Building and Courthouse this morning, some spectators outside shouted, ''We love you, Oprah!'' -- and the city is just as clearly enjoying its brush with a celebrity. The Amarillo Globe-News reported that Ms. Winfrey was spotted Monday night at Ruby Tequila's Mexican Kitchen, a local hangout, where she ate the ostrich fajitas.

Even the Texas Beef Group, an industry organization working with the plaintiffs, said in a pretrial filing: ''Everybody is clamoring to meet Oprah and attend her shows. Amarillo is looking forward to her visit, and the plaintiffs are no different.''

The television show at issue arose from publicity over mad cow disease, a brain-destroying disorder that has led to the slaughter of 1.5 million cows in Britain and is believed to have killed 20 people who ate infected beef. Many scientists believe it was contracted by cows who were fed ground-up body parts from sheep that had the disease.

On Ms. Winfrey's program, Howard Lyman, once a fourth-generation Montana rancher and now a prominent campaigner against meat-eating, said an outbreak of mad cow disease in this country ''could make AIDS look like the common cold.'' He noted that at the time, many cattle were fed ground-up animal parts.

''But cows are herbivores,'' Ms. Winfrey replied. ''They shouldn't be eating other cows.''

Mr. Lyman responded: ''We should have them eating grass, not other cows. We've not only turned them into carnivores, we've turned them into cannibals.''

The day after the program was broadcast, cattle futures prices dropped more than 10 percent, from 62 cents a pound to 55 cents; they took weeks to recover. Whether the plaintiffs can show that Ms. Winfrey caused the drop is uncertain: futures for other commodities also took a sharp drop that day.