Christina Websell wrote:
You'll need to dust the hens with an appropriate insecticide
(especially in the "armpits" under their wings)
~That is pointless against red mite. They hide in the crevices of your
henhouse, come out overnight to feast on hens and are back before you are
up.

Nick actually noticed during the middle of the night, and spent an hour in
darkness dusting everything in sight. The garden stinks, the red mite dust
powdery stuff is incredibly sickly smelling!

for a couple of days after dusting you should discard the eggs.
Dusting will not get rid of red mite so you can ignore this advice.

But now they're dusted, presumably we should follow it? I'll get Nick to
check what the bottle says. It would be a shame to lose the first 2 eggs of
the new chicken. :-(

Whenever you introduce new birds it's always worth inspecting for
mites/lice and dusting them,to avoid infecting a clean flock.
I agree. Red mite is a different thing, though. Most hen keepers will get
red mite in the summer hiding in the crevices. They do not like phenol
though. I'm successful at the moment by using 50% Dettol in a spray bottle
into those crevices. It needs to be done 3 times at weekly intervals to
interfere with their breeding process.
Red mites cannot survive that. Or so I've found.

Sounds good. Nick wants to take the whole thing apart and disinfect it and
re-roof it, so if he can do that later this week then give them anotehr go a
week or so later, that timetable works quite well for me!