NEW YORK (CNN/Money) - Weaker-than expected sales at Apple Computer could take a bite out of stocks Wednesday.

U.S. stock futures were down in early trading, indicating a lower opening for stocks, after Apple (Research) reported the disappointing fiscal fourth-quarter sales after the market close Tuesday. Futures slipped further after the U.S. Energy Information Administration said it sees higher oil prices in 2006, as well as a 48 percent rise in natural gas heating bills this winter.

Shares of Apple were off $4.24, or 8 percent, to $47.35 in pre-market trading on Inet early Wednesday. Art Hogan, chief market analyst at Jefferies & Co., said that while Apple's numbers were clearly strong on a year-over-year comparison, the report did start to raise concerns about there being a slowdown in consumer spending heading into the all-important holiday shopping period.

"I don't think that's what happened here, I think that will be more of a fourth-quarter issue," said Hogan. "I do think we'll see some backup in consumer discretionary spending. That's something we're going to be listening to on 4Q estimates."

Hogan said the softer-than-exepcted Apple sales were due primarily to production contraints cited by the company that it said caused a huge backlog in orders for its new iPod Nano. Hogan and an analyst who covers Apple agreed that expectations for the company's quarterly report had gotten so high, investors were sure to seize on any dents in the numbers.

"Given where the stock was, they had to produce a flawless quarter and they didn't," Shaw Wu, an analyst with American Technology Research, told CNN/Money Tuesday evening after the earnings report. "They had some weaknesses on gross margin and revenue, and iPod and Mac units coming in below what investors were hoping for."

There were some strong results reported for investors, as chipmaker Advance Micro Devices (Research) posted a gain in earnings, rather than the forecasted decline. But its shares were down 4 percent in pre-market trading on Inet.

Oil prices were higher in Wednesday trading. The November light crude futures contract for NYMEX gained 34 cents to $63.87 a barrel in electronic trading, while the November contract for Brent crude rose 35 cents to $60.43.

Major markets in Asia closed lower Wednesday on the sales news from Apple. Major European markets also were lower in early trading.

Treasury prices were lower, raising the yield on the 10-year note to 4.41 percent from 4.39 percent late Friday. The dollar lost ground against on the euro and the yen.

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