Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Tyson Foods (NYSE:TSN) were getting tossed aside today, finishing down 10% on a disappointing earnings report. 

So what: The nation's largest meat processor came up short on the bottom line, posting earnings of $0.60 against expectations of $0.63. Sales were actually stronger than expected, increasing 7.7% to $9.03 billion to beat estimates of $8.84 billion, though management noted weak demand in China and challenging weather in the quarter. Tyson also said it expected domestic protein production to be down 1% for the fiscal year, primarily because of reduced hog supplies, which are expected to fall 4%-5% because of a deadly hog virus.

Now what: Despite the reduced pork production, Tyson guided sales at $37 billion, well ahead of estimates at $35.9 billion, but profit guidance was vague and on the light side as CEO Donnie Smith predicted earnings of "at least $2.78 a share." Analysts had been expecting a per-share profit of $2.92.  Even so, I'd say today's sell-off seems exaggerated given the strong sales guidance, and growth in its core chicken sales. Steps to build out prepared foods and adjust production in China according to demand also seem like the right long-term strategy. Before today's slide, Tyson shares had been bid up more than 20% on hopes for an acquisition that fell through, so today's reaction may also be a correction from that news.