The U.S. Agriculture Department began expanded national testing for mad cow disease this week — and federal officials say it’s likely another case of the disease may be found in the U.S. An Iowa spokeswoman for a cattle industry promotion group says the concerns over the new round of testing are just the latest of several issues the industry has faced recently.She says 2003-04 has “just really been a remarkable period of time for the beef industry.” Nancy Degner of the Iowa Beef Industry Council says they’ve had some real ups and downs and says they’re thankful for the knowledge of consumers on the nutritional value and safety of beef. While the discovery of the first case of mad cow disease was a negative for the industry, the Atkins and other diets spurred sales of beef. Degner says the increased sales are nice, but they’re not pushing people to survive on just beef.She says they think it’s great that people are eating more protein, but she says they’ve long supported a balanced diet with moderation, even when it comes to eating beef. Degner says that’s the approach they take for dieters and non-dieters.She says they’re still approaching it as you should choose lean cuts and eat moderate portions. While Thanksgiving and Christmas are big holidays for the turkey industry, Degner says the summer holidays are big for beef. She says Memorial Day, the Fourth of July and Labor Day are probably the three biggest beef eating days in the whole year. She says that’s because people do a lot of grilling on those holidays.