One of our girls has been laying bad eggs for several weeks. One end has a very thin shell that is discolored and moist. The rest of the shell is a bit thin but otherwise normal. The hen is 2 years old and has always good egg layer in the past. We may have fed them too much broccoli leaves, which they loved. Since this issue arose we limited the diet to egg layer pellets and offered free choice oyster shell calcium, but there is no improvement. The other girls are laying fine. Any ideas on what to do?