I had a hen I put into a cage, as she was being picked on by the others and needed time to grow back feathers and fatten up some. I kept her in the horse barn. One morning I heard a rooster crowing, much like a young rooster just learning to crow. I have a few roosters around, but all mature. The sound was coming from the area near the cage, so I went and looked. Sure enough, the HEN crowed again while I was watching her. She repeated this for about a week, and during this time she didn't lay any eggs. Then she quit it,and started laying eggs again. She repeated this again a month or so later, Started crowing and stopped laying eggs. Then stopped crowing and started laying eggs again. Thiink she was having a gender identity crisis??? Well, just before I decided I should move her back with the other hens, a racoon broke into her cage, and she was toast. This hen was hatched last year. I have heard and read about hens changing to have rooster habits, and had it happen a few year back to an old hen. She grew a larger comb, grew spurs and started to crow.
Just yesterday, I saw a different hen, an Austra White, mounting another hen like a rooster would. First time I've ever seen any thing like that. Even that older hen that developed rooster characteristics didn't do that. This hen has not crowed to my knowledge, and she doesn't seem to have any change in traits to make her look like a rooster. She's two years old. Maybe a lesbian hen? I'll keep watching. You can read about the hen changing to a rooster on the feather site, I had learned about this happening from my Ag teacher in HS years ago. I recently changed my feed to a pellitized layer mix, and I'm beginning to wonder if there is some hormone added or something. I'll have to check it out.