The jury could get the case as early as Wednesday.
The cattlemen are suing Winfrey, her production company and a vegetarian activist for up to $12 million in losses they blame on a 1996 TV show that suggested U.S. cattle could spread mad-cow disease to humans.
U.S. District Judge Mary Lou Robinson rejected defense requests to dismiss the case.
A week ago, she dealt a heavy blow to the cattlemen's case when she said the lawsuit could not go forward under Texas' "veggie libel" law, which protects agricultural products from false and disparaging remarks.
Instead, the jury will consider the lawsuit as a common-law business disparagement case, meaning the cattlemen will have to prove not only that Winfrey's show was false but that she meant to hurt the beef industry.
Bettina Whyte, an expert on court damages, was the last defense witness Tuesday as attorneys for the cattlemen questioned the accounting methods she relied on in testimony the day before.
Whyte had testified that said the cattlemen actually made money when the beef market plunged after Winfrey's show because they were able to buy livestock at lower prices.
After the defense rested, cattlemen recalled Wayne Purcell, an agricultural economics expert at Virginia Tech who questioned Whyte's use of daily cattle prices instead of weekly averages in her calculations.
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