The Dutch version has "Vlaamse reus" (a kind of rabbits, and you may recognize the second word from Rebekah's last name - it's indeed a breed of very large and sometimes really enormous rabbits) and "Vlaamse gaai" (some bird), so it managed to preserve the ethnic link in the names while still having an animal in more or less the same category as the guinea pig, and a bird. Thus allowing the preservation of the comment of Neville's guinea pig still having feathers.

This translator seems to have an obsession with the word "Vlaams" which I'm not sure I find entirely flattering. He also translated "Gobbledygook" by "Koetervlaams" - the normal word is "Koeterwaals", which he then changed with a pun on Belgian linguistic politics that I don't really see the point of.

In translation it's a pun on the Dutch national radio and television news network, which is amusing but seems a bit misguided - HP is set in Britain, obviously you have to translate things and try to conserve the jokes, but references to the Netherlands that aren't there in the original don't seem like a good idea.