The collapse of securities firm MF Global has caused big investors to make sure that their assets are better protected against a trading partner's potential failure, a Federal Reserve survey said.

The central bank on yesterday released the results of its quarterly Senior Credit Officer Opinion Survey, a report introduced in 2010 that looks at credit conditions for big investors in the securities financing and derivatives markets. The report found that the October 2011 collapse of MF Global has sparked increased worries among investors.