Donald is wearing his sailor suit instead of the tuxedo shirt he bought earlier when the ball and chain appears.
When Gladstone's ball and chain appears, the chain links are of a different style than in the rest of the episode.
During the flashback where Gladstone apprehended a Beagle Boy (Burger), Donald is wearing his black sailor suit even though he's suppose to be wearing his blue one, though it's possible that this flashback occurred around the time he was still adventuring with Scrooge.