We have a 17 month old Rhode Island Red hen that has lost much of her head feathers over the last three months. We also noticed her back and neck feathers appear to be wet when they are actually dry. There are three other hens in a 36 square foot coop the same age as this little girl and none of them are showing signs of loosing head feathers, or starting their first molt. However, this hen may have stopped laying too, we just can't tell yet because we get three eggs a day in the winter when we used to get four pretty consistently. We have considered their diet and have them on Purina Layena Crumbles since they were 24 weeks old. Also we have not seen any bullying, or pecking on this hen she seems to be the darling of the flock. Any idea what's going on?