I tried the pyrithione, but it failed over and over.
Ultimately, I found a treatment that actually worked. I got powdered Sevin (carbaryl) in an old dock and as I grabbed my chickens by the feet, I powdered their vents, under each wing (arnmpits?) and let them go into their run.
I took mineral oil and wiped down their roosts and cleaned out all the shredded hay in the coop and laying boxes.
When I put them in for the evening, I sprayed their legs and feet with mineral oil again.
The next morning, they were released normally into the run, but had to take a few steps on an old terrycloth bar towel, soaked in new transmission fluid. It's red, so I could see it on each bird's feet.
The mites live on the perches by day and wait for dark to re-infest the birds. It's a losing battle to not kill the mites so they can't keep the cycle alive.
Oil of pretty much any kind will smother the bloodsucking mites. It clogs their book lungs and they suffocate.
The Sevin/Cabaryl has a very short half life and you can pretty much put it on your Cheerios.....it's that safe and totally non-residual.
I use the dust as a preventative to insure against wild birds bringing more mites into my small flock. My wife and I had 4 flocks of 25-30 birds each when I first married her, and this is the same technique that I used on all those birds too.
We only lost three hen's to a cross-sexed perverted horny rabbit that ripped the necks of our hen's when he had sex with them.
Crazy rabbit! He died via a .410 shotgun.
Addendum...
The development of the carbamate insecticides has been called a major breakthrough in
pesticides.
The carbamates do not have the persistence of chlorinated pesticides.
Although toxic to insects, carbaryl is detoxified and eliminated rapidly in vertebrates.
It is neither concentrated in fat nor secreted in milk, so is favored for food crops, at least in the US.
It is the active ingredient in Carylderm shampoo used to combat head lice in children and adults.
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