One of my ducks has not molted and her feathers are in terrible condition. She is two years old. She continued to lay very fragile eggs all winter - half the mornings they are broken in the coop, and when they're not, they are very thin-shelled. She's has this habbit in the past few months where in the morning when I let my ducks into their run, she runs over by me at the door and grabs a couple bites of dirt from outside. Most of my other ducks run straight for the oyster shells. I just recently realized she doesn't eat the oyster shells at all. I stopped her from grabbing dirt to see if she would go for them, but she doesn't....she just digs down in the run trying to get the dirt below the pea gravel. I started giving her 1 ml. of calcium gluconate a few days ago, but I don't know how long it's okay to keep that up, or if it will even help. I also started finding a broken soft shelled egg in the evening in the run recently before they go to bed, and I don't know if that's her as well. Anyone have any advice as to how to make sure she gets adequate calcium or how long I can continue to safely supplement her? My ducks eat a mix of breeder and maintenance Mazuri waterfowl feed.