Yes
Yes, per the Cincinnati Zoo website (http://cincinnatizoo.org/zoo-today/): "The Zoo is open January 1st – December 31st at 10am. The Zoo is closed on December 25th only." The Zoo also may occasionally close all or some attractions for inclement weather such as storms or excessive heat or cold. I know they are also open outside their usual hours for member early entry, special events, classes and privately reserved events.
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