Updated from 11:33 a.m. EST

Shares of PetsMart ( PETM) were among the Nasdaq's losers Tuesday, falling 4.6% after the company trimmed fourth-quarter comparable-store sales and full-year earnings guidance.

The pet-supplies company now expects full-year earnings of $1.16 to $1.17 a share, down from previous guidance of $1.19 to $1.20 a share. The forecast includes a pretax gain of $3.6 million from a legal settlement. PetsMart now expects comparable-store sales growth of 5% during the fourth quarter. Analysts surveyed by Thomson First Call had been expecting full-year earnings of $1.18 a share. "Like many retailers, we experienced a slower-than-expected holiday selling season, but results improved as the quarter progressed, and we are now back to normal levels of traffic and sales," the company said. PetsMart will post its fourth-quarter results on March 2. Shares traded down $1.53 to $31.71.

Krispy Kreme ( KKD) rose 10.2% after the troubled doughnut maker announced the ouster of CEO Scott Livengood. Stephen Cooper, a turnaround adviser who currently acts as interim CEO of Enron, will replace Livengood. Steven Panagos has been named president and chief operating officer. Cooper is the chairman of Kroll Zolfo Cooper; Panagos serves as managing director. Krispy Kreme said that Livengood would become a consultant to the company on an interim basis.

In addition to the management changes announced by the company, Krispy Kreme said that fourth-quarter results have been "adversely impacted by significant sales declines." For the eight weeks ending Dec. 26, 2004, systemwide average weekly sales declined 18% and company average sales declined 25%. The quarter, Krispy Kreme said, is also being hurt by costs associated with previously disclosed legal and regulatory matters. As a result, the company may post a loss during the fourth quarter. Analysts had been expecting the company to post a profit of 5 cents a share. Shares traded up 89 cents to $9.61.

Shares of Alcan Aluminum ( AL) fell 5.3% after the company warned that fourth-quarter earnings would fall below expectations. The aluminum producer expects operating income to drop 30% from third-quarter levels of 74 cents a share. Analysts had been expecting earnings of 74 cents a share. A seasonal slowdown, falling dollar, and higher fuel and other energy-related costs hurt the company's fourth quarter. Shares traded down $2.48 to $44.40.

Parker Hannifin ( PH) fell 10% after the company posted second-quarter earnings that missed expectations. Excluding items, the industrial products maker earned 94 cents a share on sales of $1.94 billion. Analysts had been expecting earnings of $1.03 a share on sales of $1.9 billion. Looking ahead, Parker expects third-quarter earnings of $1.10 to $1.30 a share, in line with expectations of $1.24 a share. Shares traded down $7.34 to $66.09.

Shares of Georgia-Pacific ( GP) fell 4.4% after the company warned that fourth-quarter earnings results would fall below expectations. Excluding asbestos-related charges and other unusual items, the paper and tissue manufacturer expects earnings of 45 cents to 50 cents a share, below analysts' estimates of 57 cents a share. Weaker-than-expected results in the company's packaging and building products contributed to the earnings shortfall. The building products segment was hurt by maintenance downtime, which was postponed to the fourth quarter as a result of strong demand during the first three quarters of the year, and limited wood supply due to seasonal weather conditions, it said. Shares traded down $1.55 to $33.99.

NYSE volume leaders included Lucent ( LU), up 19 cents to $3.70; Nortel ( NT), down 8 cents to $3.24; Pfizer ( PFE), down 1 cent to $25.24; Pfizer ( PFE), up 5 cents to $25.30; Motorola ( MOT), up 40 cents to $17.43; Advanced Micro Devices ( AMD), up 34 cents to $15.50; General Electric ( GE), up 44 cents to $35.96; and May Department Stores ( MAY), up $4.37 to $32.21.

Nasdaq volume leaders included Sun Microsystems ( SUNW), up 23 cents to $4.45; Microsoft ( MSFT), up 20 cents to $26.32; Intel ( INTC), down 8 cents to $22.94; Oracle ( ORCL), up 15 cents to $13.78; JDS Uniphase ( JDSU), unchanged at $2.78; Cisco ( CSCO), down 14 cents to $18.74; and Sirius Satellite Radio ( SIRI), down 21 cents to $6.24.