What are these bugs? Mites?

hi all,

https://drive.google.com/file/d/0B18vUDxbkHLXeXZJX0lMVW5aNXM/edit?usp=sharing

Are these mites? i went and bought Johnsons mite and lice powder a few days ago after seeing these. I then Cleaned everything out of the chicken coop and locked the chickens out. i then washed it all down with water the whole place, i then powdered all and each 11 chickens by hand to ensure they where all dusted all over. After all that i let the coop dry thanks to the very hot weather, powdered all insdie the coop and on the hay they use to lay eggs. and still after 2 days i still get covered in them... what are they!! and how can i get rid of them thanks!!!