I wouldn't. I'm sure youCANbut I know in looking into doing things like a whole chicken or even a turkey it isn't recommended because by the time the dark meat is done the white will be ruined (or vice versa). I don't know much about cooking duck but I wouldn't risk ruining it and souring yourself on sous-vide cooking by experimenting on it.
Go find the biggest thickest ribeye you can find and cook that about about 130*F (for medium rare) for 2 hours or so. Then after that do the same thing with a bone-in pork chop.