Pyrethrin dilution for fleas

[slmwatts]

I have been battling stick tight fleas for a couple of years. Cannot seem to totally eradicate them. My flock is free range and we lock them up at night in a wire coop. I read here on BYC to use Adams Flea and Tick Spray on the birds (cotton ball soaked and dabbed on affected heads and vents) so I did that and sprayed the coop/boxes and surrounding areas with liquid Sevin. The Adams was great, but it was an old bottle I found in the barn. It was Pyrethrin. The Adams I find in stores now is not. So I bought Adams Flea and Tick Yard spray which is 2.5% permethrin. Anyone have a suggestion as to how much I should dilute to apply using my cotton ball method? (Is there a dangerous level of permethrin to chickens?!) Or any other suggestions for eradicating the terrible fleas?!

 

[EggSighted4Life]

The dilution for permethrin in the spray I use, labeled for chickens is 0.5% applied directly to the skin... no egg withdrawal (or soaking chicken) required. Found in the equine section.. under many brand names and concentrations. Has been very safe and effective at my place for red mites and poultry lice.
https://www.horse.com/item/fly-rid-plus-spray/E006407/

Sorry, I do not have the calculation on hand to reach your desired dilution level.