Cochins are laying bumpy textured eggs o-o

[Moochie]

Some of our cochins starting to lay are laying small, bumpy, ridged, textured eggs. I just call em' "retard eggs". My mom says that they may not be getting enough calcium in their diet. We have alot of chickens in our frontyard, around 30, and the "5" (our first original girls, now hens) are at the top of the pecking order and get most of the treats. We are fair with treats but they are the fastest and they take the biggest chunks of whatever we give them. When I call Moochie, yes she does respond, for worms or somethings I find in the dirt she eats a ton!
The weather has been cold and it just rained a day ago so what can I give them that's good cold weather food?
Also one of the cochins had that one egg problem... I forgot the name!!

Anyways in the area where they sleep I found a soft mushy eggshell and yolk everywhere.

 

[chicky_mommy]

you may want to mix oystershell with their feed, i started doing this when my cochin first started laying after about 6weeks i stopped giving it to her and for the most part the problem was solved but i still occasionally got a "weirdo" egg, as my little sister liked to call them, that was just kind of oddly shaped i think it was just from the bedding mostly you know it sort of molded to the bedding while it was still soft and warm...

others on here may have other ideas as to what you can do...