I can't find any sound moral justification for acknowledging the interest of one species while denying it to the other

I respect an animal’s interest in continuing to live, per se, for the exact same reasons I respect a human being’s interest in continuing to live. I can’t find any sound moral justification for acknowledging the interest of one species while denying it to the other. Can you?
~ Matthew Finateri (April 7, 2010)