I have young pullets that are 7 months old. They are auracanas, barred rocks, buff orphingtons and rhode island reds. They are just starting to lay. In the last couple of weeks I have had some die. I have approximately 75 total. A couple of weeks ago I lost a couple of the Buff Orphingtons. Yesterday I lost 2 Rhode Island Reds, 1 Barred Rock and 1 Auracana. They are all in very good shape. I'm feeding them a 16% protein laying crumble along with hen scratch. They get 25 lbs of crumbles and about 3 to 5 lbs of scratch per day. They all appear very healthy. Their chicken house is 12' X 12'. Their chicken yard is 12' X 48'. They don't go outside of this chicken house and yard. They're given plenty of fresh oyster shell. It appears they are dieing right after they lay an egg because their vent is open widely when I find them. A couple were found in the yard and some have been found just outside the nesting area. I found an auracana flopping around yesterday just before she died. She had been fine earlier. I had seen her in the nesting area and later I saw her in the chicken yard flopping around. When I picked her up she died. I then looked at the vent area and it was very stretched out just like the others. There were no large eggs found. All the eggs look normal ( meaning I haven't picked up any double yoaks ). Most of the eggs are of pullet size. I have raised chickens for several years and have never run into this problem. The first couple I thought maybe they were egg bound but now that it has happened several times I'm now at a loss for ideas.