Ammonia smell in coop-first time owner

[binka]

We got them about 6 weeks ago and her ear was fine then. Today I noticed that one ear no longer has any fur on it and there is like white, patchy circles on the skin. Other ear is fine and she is otherwise well? Any ideas what it is?

[Solopuff]

Sounds as though it could be a fungal infection ie ringworm.

I have treated this before using an anti fungal cream like Daktarin or Canestan. Just rub it into the affected ear twice a day. Keep going for several days once the ear seems better just to make sure you have completely cured the problem.