We added 10 chickens and 1 guinea fowl to our flock about one month ago. They were all around 1 year old. My 3 hens I already had are 1 1/2 yrs old and 9 months old. I knew that I would have thin shelled eggs or shell less eggs due to the stress of adding/moving chickens. This has happened. I countered with having crushed oyster shell in one feeder, giving them pumpkin, squash and cottage cheese. They won't eat the oyster shell--they totally ignore it. The pumpkin, squash and cottage cheese are gone in no time. They get this a couple times a week. I am feeding them Dumor crumbles, treats of cracked corn and the aforementioned extras as well as veggies. The eggs are still thin shelled, wrinkled and occasionally a shell less one. What am I missing/doing wrong? One of the hens did die suddenly about 3 weeks after I got them. The others have shown no sign of problems.