scaby chicken

I noticed about 3 days ago my buff orpington has a patch of feathers missing from the base of her tail going onto her back. Looked at her tonight and it looks quite sore and it has been bleeding. Is it the result of fighting with my other hens? Or could it be something else?

Thanks for that, I have never heard of that spray do you know where I can get it from cheers .

You might also check her under a bright light, particularly at night, to see if she has mites or lice~check around her vent area....her picking and attempting to rid herself of the itch of it all can lead to bare and scabby skin.