I have about 40 chickens at least 15 have big bright red butts with no feathers like area size of a grapefruit.I have dusted all of them at least 4x a week apart ,I scrap the coop everyday dust with all kinds of products as well as de change out bedding daily have a cement coop floor dust and scrap all roosts have used many products in their dusting holes in the yard they have more than enuff space inside and out and have used 26% game starter for several months to increase protien no luck.And many of them show no problems at all.I have also came out after dark and inspected roosts and chikens for bgs nothin what do I have.My coop is so clean
