I lived inside the Hoosier National Forest and my chickens were not enough evidently.They way I understood it was you spray the inside of the tube with permethrin and just let them run through it and it kills the tick larva on them, they don't need to take anything from the tube to get treated. We have bad deer ticks and lymes disease where I live, but once we got chickens and started letting them free range, I haven't found one from my own property for at least two years, used to be that we would find a handful of them on us and the dogs everyday during the summer. I've definitely never found one on one of our hens. But, to be honest, I'm not really looking.
The mice are supposed to carry the cotton balls (that are sprayed or soaked in permethrin) back to their nest and the permethrin is then transferred to their little bodies as they move the balls of cotton around inside their home.