One chick is significantly smaller and very dopey!?!? Anyone know what to do?? **pictures**

[nlbeardmore]

I have 4 chicks, 3 of which are Buff orps and the one which i am concerned about is a buff columbian. She acts very dopey and will often stay in the same place all day with her eyes closed and tweeting and rocking. Her wings look like they are dropped and she looks very puffed up, although when i pick her up she is just skin and bone. She has a very small appetite but will eat and drink. The other chicks are now outside with the rest of the chickens as they have all their feathers, I put the buff col out when occasionally but worry she is cold as she does not have her head feathers through. She has always been like this but now i am concerned as she is not keeping up with the others. They are all 8-9 weeks of age! Does any one know if it is because of her breed? Or if she has something wrong with her. I can just go up to her and pick her up and she doesnt move. Here are the pictures which show her size difference against the girl Buff orp we have




Please can anyone help?

 

[chookhead]

i think this is better posted in the diseases section of the forum but it seems like a cocci infection but i am not an expert, post it in the diseases section and they should be able to help u be quick