Nothing Stays the Same In the End

Hello wonderful people!

I've got a fantasy story that's set in early 18th-century Venice. I don't speak Italian, and definitely don't know the difference between the various regional dialects, so I'm looking for some help with a nickname in Venetian.

I have a priest who can use magic, who is not exactly a nice guy. Nobody likes to be around him, he's the kind of person you can just tell will erupt like a magic-spewing volcano the moment something doesn't go his way. My main character is ten when she first meets him and has a very visceral Do Not Like reaction to him, comparing him to a pack of rabid dogs. She is not told his name at the time, so in her mind she dubs him Father Mad Dog (creative, I know).

Several years ago I tried to parse "Father Mad Dog" into Italian/Venetian, and I don't know where I came to the conclusion that it'd be "Don Can' Pazzo" but that's what I've been using. I guess somewhere along the line I was under the impression that cane would get shortened to can when used like this. Is any of this correct? Or do I need another phrase entirely?