'Wak!' tended to be Donald's choice of surprised exclamation.
I prefer Scrooge's 'My little stars and comets!' or (even better) 'great honk!'
Back in the eighties and ninties, I used to go to a local comic store to get a subscription of US Disney Comics (published by Gladstone). Eventually (I seem to remember when the publishing was taken over by Disney themselves) these comics could no longer be sold in shops in the UK. I was told this was because 'Disney UK' were worried that 'Disney US' were stealing their comic sales - doubtful due to the limited availablility of the US comics and the relative child-friendliness of the UK versions. I had to begin subscribing to the US titles direct form the publisher - something that had to cease when I moved out from my parent's house and had other things that I had to spend my limited income on (ie food and shelter).
I know that since then, US Disney comics have suffered many slings and arrows and have never really kept a decent foothold in the market. Meanwhile, UK Disney comics are aimed squarely at pre-schoolers.
All of the best Disney comicstories of recent decades have been produced or commissioned by Disney's European comic producers (including works by leading US 'duck-man' Don Rosa) and DLP should really reflect this and celebrate what seems to have become a large niche in a dwindling market.
As you may tell, this is one of my passions and I must apologise for upsetting this thread and bringing it so far off topic. From rats to ducks eh?!