Can you please tell us more? There's a sticky post, the second one on the emergecies/disease/etc forum, that has a list of questions that we need answered to be of more accurate help for you.
In the mean time I'd add these. If you'll please do me the big favor of answering them all as I've chosen them specifically for your bird. It'll really help.
First, does your bird have access then to puddles/ponds, etc? If so, are any of them downhill from your barnyard, the poultry yards, etc? In other words, is it possible that any droppings have gotten into the water?
Do you have a compost pile, or any place where the bird could have gotten into vegetable scraps, decomposing vegetation, or the water run off from any of those?
Any algea puddles or ponds in the area?
Do the birds free range in a treed area? Any possibility of coming in contact with maggots or an overload of earthworms?
What are you feeding? did any of the feed get wet, even just misted? Any wet grains?
Feel your bird and examine her carefully: are there any droppings clinging to her vent? Is her keel (breastbone) sharp? Is she pale in the comb? Check very carefully for parasites (mites, lice, nearly microscoping anything - their eggs, etc) along the feather shafts, body, and particularly near the vent of your bird. Parasites love the warmth and moisture of the vent area. Use a flashlight and/or white sheet to facilitate your search. Tell us what you do or don't find.
Were your chicks vaccinated from the hatchery, or were they swap or local purchases? Was this hen of vaccinated stock, or local/swap?
Is there any possibility that this hen has been bullied away from food/water? Will she eat now?
Can you feel anything mushy in her crop? Does it empty over night?
Do your birds get wormed once or twice a year? Or have they ever been?
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Now you'll want to make sure she's getting nutrition as her ataxia (drunkenness) can be a sign of anemia or dehydration. Make a mash of plain yogurt, a boiled mashed egg yolk, her crumbles, and water. You can also add a little applesauce (baby food applesauce is idea but regular will do). Give that to her to encourage her to eat. Take a little of it and mix with water til it's just thicker than water but barely. Dribble this into the side of her beak and let her swallow it. Do NOT put it down her throat, but putting it at the side of her beak allows her to swallow it on her own. That "jump started" water filled with nutrition will help her have fuel to overcome what she has if she can.
Yogurt will provide living bacteria to help get the gut back into shape. Bacteria are the workers that literally nourish your bird. They're essential. Any bird that is stressed, medicated, ill, or wormed should get some. Use the same amount that would be a serving for the bird for their size if they were a very very short human.
In other words, a cup of yogurt for me would be about a thimble of yogurt for a small bantam. It doesn't have to be exactly - but don't give that bantam a half cup of yogurt - even if they beg - because it would then be too much.
Egg yolk is full of fat and nutrients concentrated. They dissolve very easily when boiled (which is why I don't recommend scrambled) and won't clog a slow crop. They also provide protein which, until we decide the bird might have coccidiosis, can be useful.
Applesauce corrects the pH of the digestive tract to be better for good bacteria, bad for bad bacteria. The pectin of applesauce cleanses the gut gently while feeding the good bacteria who will in turn feed your bird and protect it from bad bacteria. Plus birds love the taste. It's a good way to hide yogurt and other good-for-them foods. Use it to where you barely moisten the food - not to where it's sticky. Birds are often offended by too-moist food.
The crumbles are nutritionally balanced and easily dissolve, again not blocking her crop. I'd not feed grains or let her free range for now. Nor would I feed her bread or anything other than the above listed very easily dissolved foods. If your babies are eating medicated (amprolium only) crumbles - use those to feed her for a few days. Your babies will also benefit from this same mash mixture especially the probiotic yogurt to heal and prevent further coccidiosis problems. Then put them back on their age-appropriate food.
Start her on this recovery diet and please answer our questions. In return, we'll do our very best to give you accurate help.
p.s. I'm a bit disturbed by the yellow coloration in her urates of her droppings. They should be very white. And the dropping on the right seems to have either a big of rusty mucousy discoloration reminding me of either intestinal sloughing, coccidiosis, or a bacteria infection (thus my million questions - to differentiate).