CHICAGO, March 16 (Reuters) - Chicago Mercantile Exchange live cattle fell on Wednesday on technical liquidation, as livestock markets continue to wrestle with questions about consumer demand as food prices surge, traders said.

Feeder cattle futures firmed on the day as feed prices fell, traders said.

"Today's live cattle futures trade has been choppy to weaker, as traders wait for activity on the cash market," Arlan Suderman, StoneX chief commodities economist, said in a client note. "The expectations are for trade to emerge near $140 per cwt in the Southern Plains feedlot region."

Lean hog futures were mixed as livestock traders jockeyed for position ahead of the U.S. Department of Agriculture's weekly export report.

"It's a market that, with all the uncertainty in the Black Sea region, has everybody trying to stay pretty close to home in their positions ahead of the weekend," said Don Roose, president of agricultural broker U.S. Commodities.

CME's most-active June live cattle fell 1.275 cents to 135.525 cents per lb, while April feeder cattle rose 0.025 cent to 162.625 cents.

U.S. boxed beef prices were up, with choice cuts gaining 18 cents to $258.08 per cwt, the USDA said, while select cuts firmed $1.43 to $250.27 per cwt.

Cattle slaughter maintained recent processing pace, with 125,000 head slaughtered.

CME April lean hog futures slipped back 0.025 cent to end at 102.375 cents per pound. June hogs firmed 0.400 cent to finish at 120.475 cents per pound. (Reporting by P.J. Huffstutter in Chicago; Editing by Devika Syamnath)