Loosing feathers & eggs

[WRF]

I have barred rock laying hens that are about one year old. Two weeks ago they started loosing feathers and egg production is down 90%. Some hen exhibit bare spots on the rear ends but do not exhibit scaling or bleeding. Others have bare spots on the breast. All look extremely healthy and eat and drink normally. No signs of lice or mites. Can anyone help identify what is wrong and treatment.

 

[enggass]

Molting?