Tyson Foods Inc's quarterly earnings surged 86 percent as it sold beef and pork at much higher prices, sending its shares up 6.3 percent in premarket trading.

First-quarter earnings at the world's largest meat company were $298 million, or 78 cents per share, compared with $160 million, or 42 cents, a year earlier. The results include an $11 million gain, or 3 cents a share, for an investment sale.

Wall Street analysts, on average, had expected 62 cents, according to Thomson Reuters I/B/E/S.

Revenue for the quarter was $7.61 billion, while Wall Street expected $7.15 billion.

Our performance is due to on-going, sustainable operational improvements across all four segments, said Chief Executive Donnie Smith, Our view of 2011 is basically the same as it was a few months ago. Beef and Pork are off to a great start, and their combined results in 2011 should be similar to 2010.

The segments include beef, pork, chicken and prepared foods.

The operational improvements were primarily in chicken and include streamlining production, reducing product movement between plants, and more flexibility in producing different products.

(Reporting by Bob Burgdorfer, Chicago; NR Sethuraman in Bangalore; Editing by Gopakumar Warrier, Dave Zimmerman)