U.S. stock futures were lower this morning, with the Dow futures falling more than 200 points on Wednesday.Shares of Cal-Maine Foods Inc (NASDAQ:CALM) fell sharply in pre-market trading after the company posted weaker-than-expected first-quarter results.Cal-Maine Foods reported quarterly earnings of $4.12 per share which missed the analyst consensus estimate of $5.35 per share. The company reported quarterly sales of $922.602 million which missed the analyst consensus estimate of $960.313 million.Cal-Maine ...