So as everyone can see I am new to all this. I love my girls and do want them to be healthy. How do u know if your chickens have mites? And if they do am I suppose to treat with DE? I saw that meantioned several times. What does DE stand for? My oldest chicks are 3 1/2 months old and the younger ones are 7 weeks. All were purchased from a hatchery if that makes any difference. Thanks for all the help in advance!