Stocks were mixed with the S&P 500 barely holding onto slight gains by mid-afternoon Monday as an unexpected turn lower in crude pulled major oilers into the red. 

The S&P 500 was up 0.1%, the Dow Jones Industrial Average fell 0.29%, and the Nasdaq gained 0.46%.

Crude lost earlier highs as a rally around output disruption in Canada faded. The commodity had been sharply higher as a massive wildfire in Canada significantly reduced the country's daily output. The wildfire in Alberta has hampered more than 1 million barrels in daily production capacity as 11 producers and three pipeline operators were forced to limit operations. The reduced output is equivalent to more than a third of Canada's daily production.

West Texas Intermediate crude oil was down 2.5% to $43.57 a barrel after topping $45 earlier in the session.

Saudi Arabia's government endured a shakeup over the weekend with oil minister Ali al-Naimi, who had held the position for two decades, replaced with Khalid al-Falih. Al-Falih is a former chairman of Saudi Aramco, the state-run oil giant that is considering a partial initial public offering. Al-Falih said in a statement that the major oil-producing country would "maintain its stable petroleum policies."

Multibillion-dollar oil producers Chevron(CVX) - Get Report and Exxon Mobil(XOM) - Get Report led the Dow lower on Monday. Other non-Dow oil companies including Shell (RDS.A) , Total(TOT) - Get Report  and BP(BP) - Get Report were also in decline. The Energy Select Sector SPDR ETF (XLE) - Get Report tumbled 1.7%. 

Krispy Kreme (KKD) surged 24% after agreeing to be acquired by JAB Beech in a deal worth around $1.35 billion. JAB Beech offered $21 a share in cash, a 25% premium to Krispy Kreme's Friday close. The deal is expected to close in the third quarter.

Tyson Foods(TSN) - Get Report was also boosting the consumer staples sector, climbing 1.7% after beating second-quarter estimates and boosting its full-year outlook. The meat producer said it expects full-year profit between $4.20 and $4.30 a share, up from previous guidance of $3.85 to $3.95.

Other consumer stocks including Anheuser-BuschInBev(BUD) - Get Report , Unilever(UL) - Get Report  and CVS Health(CVS) - Get Report were all higher, while the Consumer Staples Select Sector SPDR ETF (XLP) - Get Report rose 0.5%.

Chinese markets were under pressure after trade shrank in April, contributing to worries over the world's second-largest economy. Exports fell 1.8% last month, while imports slumped 10.9%. China suffered its slowest growth in seven years in the first quarter as a manufacturing slowdown and weak global demand impacted its economy.

Sotheby's(BID) - Get Report  added 4.7% despite reporting a steeper-than-expected loss in its first quarter. The auction house said it had a loss of 41 cents a share, far wider than a loss of 7 cents in the year-ago quarter. Consensus was for a loss of 26 cents a share. Net auction sales fell 35% in the recent quarter after an especially favorable first quarter last year.

Valeant Pharmaceuticals (VRX) was 4% lower after announcing plans to file first-quarter earnings on or before June 10. The drugmaker had postponed the release as it underwent an internal accounting investigation. Valeant reiterated previous first-quarter revenue and earnings guidance.