If I can separate, and treat individually, that is my preference, as I don't like to over use antibiotics. Secondly, you're not supposed to eat the eggs from treated chickens for several weeks..and if you treat the whole flock, you're out of eggs for a while. However, if other flock mates start showing symptoms, then I wouldn't hesitate to treat them all, and forego the eggs for 3 weeks.
Its sounds respiratory to me to, based on your preliminary description. Hold her up to your ear, and listen to her breathing too. Is her mouth open a lot? Can you go bug dad and ask him about moving her in the garage tonight with a heat lamp?
Edit.... okay good! I love how fast great advice arrives!!!
You can ignore my post. LOL. I'm glad Dad said okay. Give him a hug from us...
Its to late tonight. But I will do it first thing in the morning. My dad is sleeping but my mom thought it would be okay. So when I get up 7:30 am I will work on setting up a place for her and then get mom to take me a get medicine. And hopefully a heat lamp otherwise I have to take it away from a babies and deal with their frozen water. Anyone have any ideas as to what could have caused this? So I can try and prevent it from happening again?
Oh and I will only treat the one unless others show symptoms. And I did know about the eggs!
Sometimes changes in weather can make chickens more susceptible to things. Its not always something you can prevent. Just keep up your best chicken-care practices, and hopefully this will be your only feathered patient this winter.
Reflecting hood + bulb should only cost about $10.00. It doesn't have to be one of the more expensive brooder set ups. Its worth the $$ if its in your families budget.
I'll keep my fingers crossed for you and your hen!