I just want to point out that we are animals. I mean do you feel like an animal when You eat or breathe or sleep? cuz animals do all of those things too.
*But* i didn't really get the impression that sex grosses you out because animals do it, it seems to me that it's more that sex just grosses you out and as a result you think "it's like animals". Look there could be a million reasons for this, it could be from some experience you had as a child and forgot about, it could be a chemical imbalance, or anything else, maybe it's just the way you are, who knows.
Since you said it doesn't bother you i don't really think there's anything wrong with saying "well i'm asexual and i'm totally fine with it" and leaving it at that. But it also wouldn't hurt to maybe talk to a therapist and see if they can help you figure some of it out, maybe there's some underlying issue that's effecting you in other ways too. Or you could think about going to a sex therapist to see if they can help you figure out a way to enjoy sex. As long as it doesn't bother you, i wouldn't really worry about it.