thank you for the link ...very scaryon another topic, related to why some of us are so fervent about non-chemical means of treating our flocks whenever possible: try reading this (long) article about toxins in your blood (yup, yours) from Dow Chemical.
http://www.nytimes.com/2016/01/10/m...=Full®ion=Marginalia&src=me&pgtype=article
It will help you when you are thinking that perhaps you are taking this natural approach too seriously. Because, you can't take it seriously enough.