Here are my two girls, question tho, and I also posted this on the duck forum, one is laying a soft shelled egg daily. They are 15 mnths old, no change in diet since POL, layena with free choice oyster shell. No change in behavior. Everything is normal except her eggs. The other is just fine. Im baffled. Been going on a couple of weeks now. Any help is apprrciated, thank you!
I find that some ducks start running low on calcium reserves after a while. I have nine Runners. Each is unique. Some have never had a soft egg that I know of, some are regularly in need of extra calcium. For the latter, I put about 100 mg of calcium citrate (I crush the tablets) in a tablespoon or two of thawed frozen peas. I squish several of the peas - they seem to hold more of the Ca citrate that way. Then I have a secret rendezvous with the girl who gets the "special." They quickly catch on that they are getting something just for them, and they will see me coming and separate themselves from the flock.