US meat processor Tyson Foods has said it is temporarily suspending operations at four beef plants and reducing operations at one other due to unfavourable beef operating margins.

The affected plants are located in the Upper Midwest and Pacific Northwest regions of the US, and have been hurt by a combination of tight cattle supplies, lacklustre domestic beef demand and the continued absence of key export markets, Tyson said.

Tyson is, from today [Monday 10 January], suspending operations at plants in Denison, Iowa; Norfolk and West Point, Nebraska; and Boise, Idaho. The company will also temporarily discontinue second shift processing at its Pasco, Washington facility. The suspension of operations is expected to last three to five weeks and will reduce the company's weekly cattle slaughter by between 25,000 and 30,000 head, compared to pre-holiday levels.

"Our plants have been running at less than 75% of capacity over the past two months, which is 10 to 15% below historical levels," said chairman and CEO John Tyson.

"We anticipate cattle numbers will increase in the coming months," added Gene Leman, senior group vice president of Tyson Fresh Meats. "We also look forward to the previously announced reopening of the US border to Canadian cattle in early March, which will especially benefit our plants in the Upper Midwest and Pacific Northwest."

The company said it now expects its fiscal 2005 diluted earnings per share to be in the range of $1.15 to $1.40.