During my first gamefowl hatch this year (part of the 16 chicks I sold to the feed store) my hen Honey crushed the side of an egg fighting me over a chick. I left it under her and it hatched. I think it may have internally pipped before it ended up broken.
I wonder if B vitamin tablets would work for a duckling? If it hatches I know I'll need something to help it get what it needs.
Yes, I used the B vitamins. I crush a little tiny bit off a tablet and add to their water.