Cattle traded generally traded near unchanged prices levels early in Thursday's session but then traded moderately lower for the day and near the daily lows into mid-session. The market closed moderately lower on the session yesterday but near the middle of the day's range. Many traders remain concerned that domestic demand could be sluggish on the run higher in beef prices. Some traders were surprised with what appeared to be fairly aggressive buying from packers in the cash market earlier than normal this week, given weak packer margins and uncertainty on domestic demand. Beef prices are climbing higher this week, which is expected after packers had to pay up for live cattle last week and then paid steady earlier this week. Boxed beef cutout values were up 44 cents at mid-session yesterday and closed 58 cents higher at $184.82. This was up from $183.26 the prior week and is the highest beef market since September 20th. Weekly U.S. beef export sales for the week ending September 29th came in at 13,800 metric tonnes, compared with the prior 4-week average of 15,425. Cumulative sales for 2011 have reached 702,600 metric tonnes, up 35.4% from last year's pace. The estimated cattle slaughter came in at 130,000 head yesterday. This brings the total for the week so far to 521,000 head, up from 518,000 head last week at this time and up from 515,000 head a year ago. Average dressed steer weights for the week ending September 24th came in at 855 pounds, up from 853 the previous week and up 0.35% from a year ago. Beef production for the same week came in at 509.8 million pounds, down 1.75% over year ago.