SAO PAULO, Aug 11 (Reuters) - Brazilian stock exchange operator B3 SA Brasil Bolsa Balcao B3SA3.SA on Thursday reported a slight decline in second-quarter recurring net profit, as falling trading volumes reflected higher interest rates, but still beating analysts' estimates. B3's recurring net profit came in at 1.34 billion reais ($259.76 million), above the Refinitiv forecast of 1.23 billion reais. ($1 = 5.1587 reais) (Reporting by Peter Frontini; Editing by Brendan O'Boyle) ((Peter.Siqueira@thomsonreuters.com; +55 11 56447727;)) The views and opinions expressed herein are the views and opinions of the author and do not necessarily reflect those of Nasdaq, Inc.