charles river laboratories international inc shares crl slid 6 in premarket trade wednesday after the drug company issued a profit warning for the second quarter the company is now expected adjusted pershare earnings to rise in the lowtomidsingle digits from the yearearlier period down from prior guidance of midtohighsingledigit growth it expects revenue to grow in the high single digits down from prior guidance for lowtodoubledigit growth the change is primarily due to unfavorable currency movements while its manufacturing growth rate is expected to be below the level of the first quarter the company made the disclosure ahead of the presentation at a william blair conference in chicago on thursday shares have fallen 34 in the year to date while the sp 500 spx has fallen 127