Well I would say you have lice in the chickenhouse
5% Sevindust Is banned for use on chickens these days
se the permethrin spray sold most every where. It is sold o
Amazon
I would do this: PUT ON PLASTIC GLOVES SO NOTHING GETS ON YOUR HANDS WHILE SPRAYING THE CHICKEN OR TREATING THE CHICKEN HOUSE.
first spray the chickens individual when they are locked up in chicken house in the morning, inside the chicken house
then as you spray each chicken completely and toss it out to the chicken pen
When done spraying the chickens,
CLEAN THE CHICKEN HOUSE from top to bottom.
And when done cleaning out the chicken house before adding bedding do this
take a can of kerosene and can of car oil and mix it.
Then take a paint brush and pant all the cracks in the wood with the kerosene and car oil mix good.
then add the bedding and the hens an be let back in after several hours you have let the chicken house soak up the mixture painted on the cracks in the wood.
This action should keep the lice from living.
PS as for any and all cats, they should not be around the hen house any ways.
If not lock them up till you done working on the chickens and chicken house.