Leghorns and colder weather

[Stella1964]

Are leghorns not good with cooler weather? I have 4 hens, and 3 of them are absolutely fine with the colder weather we're experiencing here (40F) but the leghorn just stays put in the coop and seems to shiver when we force her outside. What's up with that?

Also, her bottom is completely bare of feathers all of a sudden (no disease, we checked for that). Given that they are only 6 months old, they shouldn't be molting already...?

 

[SpottedCrow]

Chickens moult 3 times in their first year, so she could be moulting...
My dippy Leghorn has been moulting since July. She finished, then started again...argh!!!

You could check her for mites/lice. Check her vent and wing pits for crawly things.