CHICAGO, May 24 (Reuters) - Chicago Mercantile Exchange hog futures fell for the fourth day in a row on Wednesday, with a large supply base pressuring the market.

Cattle contracts were firm, rising on a round of technical buying.

After the close, the U.S. Agriculture Department said frozen U.S. beef stocks as of April 30 stood at 447.984 million lbs, down from 532.166 million a year earlier.

Pork belly stocks were up 39.1% at 81.177 million lbs.

CME June live cattle settled up 1.825 cents at 166.1 cents per pound, finding support from early weakness at its 40-day moving average. June live cattle futures have not traded below their 40-day moving average since March 29.

The most-active August live cattle contract rose 1.55 cents to 164.125 cents.

CME August feeder cattle gained 1.05 cents to finish at 234.525 cents per pound.

CME lean hogs for June delivery hogs dropped 0.875 cent to 79.8 cents per pound, hitting a fresh contract low of 79.4 cents per lb. The most-active July contract fell 0.15 cent to end at 80.825 cents. (Reporting by Mark Weinraub; Editing by Shilpi Majumdar)