Just days after announcing the cancellation of its planned $1.6 billion buy of China’s WuXi PharmaTech (Cayman) Inc., Charles River Laboratories International Inc. reports that it numbers for the second quarter of 2010 were down versus the same period last year.

For the quarter, net sales were $292.1 million, down 5.2 percent from $308.2 million in Q2 2009. However, profit dropped to $14.5 million, less than half the $34.2 million reported for the second quarter of 2009.

According to officials at Charles River Labs (NYSE: CRL), the company had a modest sales increase in the Research Models and Services (RMS) segment, but that was offset by lower sales for its Preclinical Services (PCS) segment.

Last week, Charles River Labs pulled the plug on its plans to buy WuXi. Instead, the board of Wilmington-based Charles River Labs has authorized the company to buy back up to $500 million of its own stock. Ending the deal, first announced in April, means Charles River Labs has to pay WuXi a $30 million breakup fee under terms of the original agreement.

Charles River Labs, a provider of outsourced laboratory and research services, had previously repurchased approximately 11 million shares under a prior $600 million stock repurchase authorization, and as of July 15, had approximately 66.3 million shares of common stock outstanding.

In January, Charles River Labs announced plans to close a facility in Shrewsbury and lay off 300 people. The company made several strategic acquisitions in 2009 and also opened a 60,000 square-foot facility in Shanghai.