About a week ago I started mixing 3 tablespoons of DE to 2 1/2 gallon container of egg maker food. I did this to prevent worms and any parasite that may bother my birds. Just yesterday I've discovered 2 of the birds having balding going on under their vent. I've been trying to figure out what to do and what is causing it. I posted a topic on here and doesn't seem anyone knows what it is or what could be causing it. So I called my feed store and they said to remove the DE from their food because that may be what's causing the irritation. She said that DE is ground up limestone. My question is this, has anyone ever had a problem with the DE causing this kind of problem? Or does anyone have any idea what could cause this and what to do about it?