Young duck will be about the same as a youngish chicken. Should be fine. The thing w/ cats is that they will usually not try too hard to eat inappropriately-sized bones. Unlike dogs, they won't work on them so hard that they break their teeth -- they'll just gnaw the meat off and leave what they don't want. So try it! If they don't eat all or most of the bone, that was a boneless meal. They'll probably have no trouble w/ ribs at all -- may not eat leg bones.
I cut up the duck, it was about the same as a chicken in regards to the bone, so not as useful as I hoped since they don't have much meat either. The wings had very little meat on them but will be fine to feed. The ribs and the sternum (I think) took up a lot of the bird so those will be good. I hope he enjoys it since he won't be getting anymore lol (WAY too expensive for the amount I can use, would be better for a smaller dog).
Yeah - wings of ANYTHING don't have much meat. Most of the meat is on the thigh and the breast. If they actually ate most of the bone on a wing I would probably give 3 boneless meals following that meal.