Presumably, anything called a 'superintelligence' would recognize the enormous moral difference between killing a human being and killing domesticated animals.
Aside from the problem that higher intelligence doesn't lead necessarily to convergent moral goals, in this context, I'd hope that a superintelligence didn't see it that way. Since the main argument for a difference in moral standing between humans and most animals rests on the difference in cognitive capacity, a superintelligence that took that argument seriously would by the same token be able to put its own preferences above humans and claim a moral highground in the process.
I think it would be difficult to construct an ethical system where you give no consideration to cognitive capacity. Is there a practical reason for said superintelligence to not take into account humans' cognitive capacity? Is there a logical reason for same?
Not to make light of a serious question, but, "Equal rights for bacteria!"? I think not.
Aside: I am puzzled as to the most likely reason Esar's comment was downvoted. Was it perhaps considered insufficiently sophisticated, or implying that its poster was insufficiently well-read, for LW?
Top ten tips for an AI bent on destroying humanity: