She looks very weak. The way she is acting reminds me of something that was wrong with one of my chickens. It isn't completely the same, as my chicken was fine one day and then suddenly was not alright. However, here is what happened with mine...
About a month ago, I went out one morning to check my chickens, and saw that my White Wyandotte bantam cock was still lying down in the corner where he slept. At closer inspection, I noticed that he could not stand or walk. When I put him down on the ground, he would just lay down, with his wings partially out and his head near the ground.
I brought him inside and placed him in a cage with nearby feed and water cups. Later that day, I found out that he could still stand, as he would stand up to eat and drink. He was very weak, though.
As the day's progressed, he got weaker and weaker. He stood less, and spent more time lying down with his head on the ground. Thinking it could be botulism, I gave him a molasses flush for 24 hours. This made him a bit perkier, temporarily, probably because of the sugar energy in the molasses. By the next day, he was just as bad as before, if not worse.
He still would not get better. I wormed him, just in case it was worms, but there was no improvement. It had been about six days. By this time, he could not eat or drink standing up. Instead, I fed him about six times a day with a spoon. I would mix crumbles and water together until it was a very thin soupy mixture. Then, I would tilt his head up, and place the spoon beneath his beak. I would lift up slightly with the spoon so that he, just barely, opened his beak enough that he would swallow some. I probably gave him 10-12 spoonfuls of this mixture a day. Mixed into the soupy mixture were some probiotics and electrolytes. About once a day, I would give him a spoonful of applesauce with lots of probiotics and electrolytes mixed in, as well as some poultry vitamins.
Meanwhile, another one of my birds was sick with a respiratory disease, so I had Tylan200 antibiotics lying around. I started him on a 4-day course of the Tylan. I administered .3ccs of the Tylan for the first two days, but dropped it to .2ccs for the last two days.
Halfway into the Tylan treatment, he began to show some improvement. He acted stronger, and began to try to stand. At this time, I was still feeding him by spoon six or more times a day. Over the next few days, he improved greatly. Maybe four days after the Tylan ended, he began to eat and drink on his own. I continued to spoon feed him a bit until I was sure that he was eating enough. Now, he is completely fine, just as perky and active as ever. I'm not sure why he got better. Maybe the Tylan200 helped, or maybe it was me feeding him and making sure that he didn't get weaker.
I still don't know what was wrong with my White Wyandotte bantam cock. I share this story because the way your bird was lying down and acting reminded me of my cock. I'm not saying that they had the same thing, but it is a possibility. Maybe you can try some of the same things that I did.
