Treatment resistant mites/lice?

[]Fiona[]

My White Star turned one year old in the late spring, and has not laid for 3-4 months. My other two hens lay fine (ranger and blacktail)

 

She is:

Wormed (Flubenvet)

Treated for lice (Diatom)

Normal behaviour, quite perky, although she sits on the nest for 20 mins in the morning then gets up (no egg)

Does not seem poorly

Does not seem egg bound as she is quite soft in that area

Eats smallholder pellets and mixed shell/grit, not much free ranging /treats

She weighs 1.9kg

She is not moulting

The other two hens lay fine so I presume nothing is lacking in the diet

 

I have gone down the whole list of what could be causing it but can't find a thing - have I missed something?

 

Could she have just finished laying at such a young age?

 

Thanks

[Eggasperated]

I don't know if there is anything else it could be with your girl but I do know one of my Black Rock crosses took about six months off laying, apart from tiny wind eggs, from the age of 9 months. Now she is over 3 and lays about 4 eggs a week.

It seems to me that chickens have a complete mind of their own when it comes to egg laying (and everything else really ).