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06/06/2009 05:12 am ET | Updated May 25, 2011

Hippo Castration Ends In Tragedy (VIDEO)

A zoo in Israel has some 40 hippos, but has been concerned that some of the more "frisky" hippos will become aggressive with one another if they aren't castrated when they reach maturity.

The measure is a risky one, as apparently hippos don't respond particularly well to anesthesia.

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