Grain and soybean futures prices declined today on the Chicago Board of Trade as traders became cautious about abroad advances posted in recent sessions.

Soybean prices dropped as much as 10 cents to $5.83 1/4 cents a bushel in the nearby December contract. Corn and wheat futures followed the decline, with corn easing fractions of a cent and wheat contracts losing about 2 cents a bushel.

On the chicago Mercantile Exchange, deliveries finished lower, with pork bellies suffering the worst declines.

The setback in grains occurred after wide price fluctuations earlier in the day, including a jump at midsession based on the prospects for snow and sleet in parts of the Midwest.

At the high, soybean futures were about 70 cents a bushel higher than at the beginning of last week.

But when local professionals began selling back contracts and taking profits, customer orders aimed at limiting losses depressed prices even further.

Part of the pessimism came from reports that 23.8 million bushels of soybeans were exported last week. The amount did not quite meet traders' expectations, although the figure almost matched the record exports of the previous week.

That discouraged buying in early dealings, despite other market factors that were considered bullish. Rains across the Midwest, for example, continued to delay soybean and corn combining and there were indications that a recent heavy downpour in the Southeast hurt crops.

The Agriculture Department said that wet conditions last week hampered harvesting. Soybean combining was reported as behind schedule, but the corn harvest was ahead of schedule.

At the close of grain trade, soybeans were 4 to 10 1/4 cents a bushel lower, November 5.83 1/4; wheat was 1 3/4 to 2 1/2 lower, December 2.67 1/4; corn was 1/2 to 1 1/4 lower, December 2.19 3/4, and oats were 3/4 lower to 1/2 higher, December 1.31 3/4.