Count Duckula/WMG

The Count Duckula we meet in Danger Mouse is not the one from Count Duckula.
It is his father. This more or less smoothes over all the alternations in characterisation with a nice, clean, in universe explanation.
 * Alternate theory: The Count Duckula in Count Duckula is the Reincarnation of the one from Danger Mouse.


 * Pretty much "unofficially official" as the creators have confirmed that the idea was that the Duckula from Dangermouse was somehow killed. When Igor tried to resurrect his master, Nanny mistook a bottle of ketchup for the blood that was needed in the ritual. By using a veggie-based product instead of blood, he was brought back to life as a vegetarian. As he does not need to hunt vegetables as such, he lost much of his aggression and other personality traits came to the fore.


 * It's actually heavily implied that, at least for 'the Count Duckula, there's actually no difference: when the current Count Duckula the __ is slain, the ritual that Igor and Nanny perform causes him to reincarnate, rather then straight-up resurrect, allowing each new Count Duckula the __ (the present Count is Count Duckula the 17th) to have his own unique appearance and personality. Of course, the Duckulas are also able to breed (sort of) like normal vampires, hence explaining both the menagerie of cousins and relatives that show up in the show (like the miserly Roarry McDuckula, a Scottish Duckula) and the more bizarre ancestors (like Lady Pintail Duckula, a female vampire duck who attempted to eat Castle Duckula).
 * This seems quite possible, although both Duckula's were shown as being obsessed with getting fame as an entertainer. Igor's reaction to this development always seemed to imply that it was a recent development, new to this incarnation.
 * This can be explained as a product of the improper resurrection. The 16th Count Duckla (the one in Danger Mouse) was into showbiz but was still a nefariously evil vampire, so Igor (perhaps reluctantly) tolerated it. But when he was resurrected as the 17th, as we all know, the ritual went wrong. This resulted in some of the previous Duckula's traits being carried over into the new one, including his obsession with show business. Without evil in him, this obsession became even more of a driving force, and one Igor could no longer ignore.