Unless you have an insanely low level of akrasia, I'd be wary of using your behavior as a guide to your values.

I'm not saying "having desires" isn't a factor somewhere, but I'm not a vegetarian so clearly I don't mind killing animals. I have no de-facto objection to eating dog meat instead of cow meat, but I'd be appalled to eat human. As near as I can tell, this applies exclusively to humans. I strongly suspect I'd be bothered to eat a talking dog, but I suspect both the talking and non-talking dogs have a desire not to be my dinner. The pertinent difference there seems to be communication, not desire.

I'm fine calling the relevant trait "being human" since, in this reality, it's an accurate generalization. I'm fine being wrong in the counter-factual "Dog's Talk" reality, since I don't live there. If I ever find myself living in a world with beings that are both (!human AND !dinner), I'll re-evaluate what traits contribute. Until then, I have enough evidence to rule out "desire", and insufficient evidence to propose anything other than "human" as a replacement :)