For the record, the peculiar way of barking Snowy (Bobby uses (at least, in Dutch) is not because Kuifje (Tintin) will recognize that weird sound but because those poor French have no "w" - it's mostly spelled "ou" or even "h". Bobby's French barks "Ouah! Ouah!" have, in Dutch, not been translated correctly with "Waf! Waf!" but with the weird combination of vowels as per above.
As a kid, I never understood what to make of that. Now you do... That's Progress!
In later books, the translators finally got it right.