I don't know what your weather is like out there but in the winter I have to offer grit because the ground is frozen and hard as a brick and snowy too. I think what impana said is true about keeping her on soft food for now giving her crop a chance to heal and shrink back to normal.. pic would be good. have you read any thing about cocci? lets see if we can find some good info before you treat for something she may not have. All the rest of your chickens are looking good though?