Scaly mites on my hens feet and legs

[Fisherbee]

Need help in what to do about my hens legs. And why do they all have this? Am I doing something wrong?

 

[DobieLover]

Need help in what to do about my hens legs. And why do they all have this? Am I doing something wrong?

Can you post pictures of a few of the hens legs?
Are any of them feather legged?
Some chickens seem to be prone to getting SLM.
There are many different treatments out there. The gentlest but sometimes the longest to get results is to just smear petroleum jelly up under the scales of the feet and legs repeating as often as necessary to keep them well covered to smother the lice.
A more aggressive treatment is to dip the legs in gasoline then letting the legs air dry. Once dry, slather them with A&D ointment.
The next day, just apply more A&D ointment.
The third day is done like the first day, gas then A&D. That is the entire treatment. This is usually done for very severe cases. If it is a very nasty case, I would start by soaking the legs is warm soapy water for about 15 minutes then use an old soft bristled toothbrush to gently clean the legs and feet running it sideways at a 90 deg angle to the scales, rinse then towel/air dry then do the gasoline/A&D treatment.
I have a feather legged rooster and now a d'Uccle hen in the coop. I spray their legs and feet with Lice Freee! spray just as a precaution about once a month or so. So far, so good.