I posted over in the Emergencies/Diseases/Injuries and cures section but thought I should ask here as well. I have one duck who is laying with no shell or membrane and I have no idea what to do or try. All the ducks get Waterfowl, layer pellets, oyster shell, and grit. All separate. I also provide a bit of BOSS and a little bit of Brewers yeast in the feed. All the others that are laying have strong shells. She has been laying for almost a year now and the first 6 months or so had perfect eggs. Then the shell got a bit tweaked for a several months. Then the last month rubber eggs mostly followed by the shell-less and membrane-less eggs this week. I have been supplementing her with a bit of dog food as well as she's a bit thin. Since I started her on the dog food (as well as a bit more yeast) I think part of her problem is not having molted in ages (last spring as I recall). But perhaps more is going on? Any ideas or tips or suggestions?