I have a sparrow problem and with that I am loosing the battle of the mites. My poor ladies have bald butts. I have sprayed the coops and put powder on the bottom of the nesting boxes. I have put diatomaceous earth in their dusting holes and under the litter in the coops. I have started dusting each chicken but I have about 200 of them and dusting each one is a chore. Anyone have any ideas?