Ok, I've tested the cheese lure and wheat lure. The rat comes and nabs the cheese, heals and then quickly runs away again, so it's not quite working. But when I tossed some wheat near rooster ir stopped running away. So there's definetly some sort luring mechanic at works here, glad to know.
Thanks, didn't know about the wheat lure - seems a bit random, but rats can eat grains too. At least it's good to know Larian does intend some way to "catch" these buggers.