My hen has some white powdery substance on her comb and some dark specks. Recently it has been raining in my area, so I thought it was just dirty. I tried to wipe it but it didn't come off. The next day I noticed some bald spots on her head near her comb. She seems normal and energetic. I'm not sure if my hen has a fungal infection or if it's due to the pecking order (I have 1 rooster and 3 hens). Please help!