I can't find any info about the difference in hooves. I know they're both odd-toed ungulates. Where did you find this information?

Zebras vocalize very differently than horses do, that's always been the most apparent difference to me.

Zebras are a member of the genus Equus, but they are in the subgenus Hippotigris.

I wish I could have been more helpful, I'll keep looking.

Ah, here's a link with answers to that question: http://www.answerbag.com/q_view.php/23454