Egg prices, the be-all and end-all for Cal-Maine Foods (NASDAQ: CALM), are still under pressure. As a result, the big egg producer’s stock hasn’t been able to churn out any gains for investors this year. The company reported fiscal first-quarter sales up 9.6% on Monday, but the stock was up only about 1% by 3:30 p.m. Let’s take a look at what’s going on with Cal-Maine.