I have an irrational phobia of parasites, particularly internal ones (as in, they send my brain into instant fight-or-flight mode, not just the simple "ew, gross" reaction most people have), but I can't say I hate them. They can't help what they are, and if I can get past my initial reaction, they're actually very interesting - some have quite complex and unique life cycles involving multiple hosts, and they have unique adaptations to living inside other animals. I think I'd have a special interest in them if it weren't for my phobia, but oftentimes I just can't get past that.
I'm not fond of house centipedes - for some reason, I find the angle of their legs and also their speed unsettling. I can't say I hate them either, though - again, they can't help what they are.
The only animals I actually hate are humans as a species, although individually, a good number of humans are decent enough.
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Yet in my new wildness and freedom I almost welcome the bitterness of alienage. For although nepenthe has calmed me, I know always that I am an outsider; a stranger in this century and among those who are still men.
-H. P. Lovecraft, "The Outsider"