What could it be?

My 5 month old white leghorn is sick. I have no idea what it could be... Wondering if anyone can help.

She wasn't acting like herself yesterday and today she wouldn't even come for treats! She is lethargic, thin, panting and has a very flopped over comb.

She did not have any bloody stools so I don't think it's cocci.

I took her to the vet today and he has her on a broad spectrum antibiotic 2x a day. He ruled out egg bound. She is running a temperature and having labored breathing. He really didn't give me much of a diagnosis other than saying she is sick.

We have separated her from the flock. She's in the sunroom all by herself.

Poor girl, she was the top of the flock and now she's all by herself. Anyone go through this with their chicken?

 

Thank you, I'll try that. She didn't want to eat anything this morning. Made her some oatmeal and she hasn't touched it. She seems very confused. Her comb and wattles are also pretty pale. Poor lil girl. I feel so bad for her. Hoping she'll turn around, but it's not looking good.

So to followup- if she doesn't turn around, and I don't want to cull her, can I drop her off at an animal shelter? I'm not sure what to do.