Exhibit 99.1 NEWS RELEASE CHARLES RIVER LABORATORIES ANNOUNCES THIRD-QUARTER 2024 RESULTS – Third-Quarter Revenue of $1.01 Billion – – Third-Quarter GAAP Earnings per Share of $1.33 and Non-GAAP Earnings per Share of $2.59 – – Updates 2024 Guidance – WILMINGTON, MA, November 6, 2024 – Charles River Laboratories International, Inc. (NYSE: CRL) today reported its results for the third quarter of 2024. For the quarter, revenue was $1.01 billion, a decrease of 1.6% from $1.03 billion in the third quarter of 202 ...