last night when i came home and checked on my chickens (they were all on their roost) underneath the roost was what looked like a fresh cracked egg on the ground beneath the roosting chickens, except there was no shell only a thin leathery or rubbery casing laying beside it. I have several pullets that are 5 months and starting to lay. Could this be normal? Do i need to put out more crushed oyster shell? They are finishing their pullet developer feed (organic), and I'm starting them on their laying ration today. Could this be the problem? My other 5 hens have been laying for a month with the pullet developer and no problems.