Kurt Tank called his FW190 "Würger", after the bird. In english, this bird is called shrike, and there is another one, which is not related to the shrike, but hunts in the same way, the butcherbird.
There is no intention of having a relation to slaughtering, butchering or whatever, and most and above all, "Metzger Bird" sound so absolutely awkward....
I am usually not nitpicky about stuff like that, but as I read that, my ears and eyes were bleeding.
Matt