Please bring her in for observation.. where you can check crop and also see exactly what droppings are or aren't passing.
https://the-chicken-chick.com/chicken-anatomy-crop-impacted-crop-sour/
Is she currently molting? When was her last egg?
I would not administer a flush without first assessing the situation.. though that may be great suggestion. What I mean or my main concern.. be make sure she is drinking since dehydration is deadly fast and part of flushing is simply pushing fluids through.
We've established she is lethargic, isolating, and diminished, if not non existent appetite.. Checking crop function and general digestive function MAY yield clues..
My personal go to *for starters* during assessment.. would be add a B complex plus a homemade electrolyte solution. I would also say offer probiotics.. it's already been established that you use acv.. is it raw unfiltered with mother? Sorry, I try not to presume anyone's comprehension and didn't see that stated.
Meal worms can be challenging to digest if complications are existing. Scrambled egg is an easily digested fantastic boost, but may not be any more appealing.
For a healthy young bird.. it isn't usually a function issue caused by small rodent consumption.. and also they may deal with some bacteria better.. The elder gal though.. her entire immune system and body are probably not as strong as in her youth.. Those are top 2 suspects.
Poison in the mouse seems not at play. They do have a limited home range..
At her age.. what is your regular feed routine including treats and supplements? What breed is she? Have you ever wormed them or checked for external parasite like lice or mites before?
Is her condition appear to be getting worse, staying the same, or improving?
A couple days to show symptoms.. SEEMS more functional than bacterial to my deductive reasoning.. but I am still learning every day.
Sorry for the delayed response. I ended up getting out of work late so waited until this morning to check her out.
This morning she was still hiding out in a nest box, looking lethargic. I was able to get her to eat some canned corn (rinsed and heating up; it’s 20 degrees out here so I try to give my girls a warm meal once or twice a week during the winter months). I also have a heat lamp for them that runs all day/night when it drops below freezing.
This morning as I was inspecting her, I placed her next to the water (which now has nutridrench in it) and she drank quite a bit on her own. I initially had to dip her beak in it but then she began drinking on her own. She seemed really thirsty.
I felt her crop and inspected her vent. Crop felt pretty empty; nothing notable other than that. Her vent looked totally normal- clean, dry, no discolorations or abnormalities. The feathers around her vent were clean, too. Physically (aside from the lethargy and puffy feathers) she looks healthy.
There weren’t many droppings in the nest box she’s been hiding out in (I suspect because she hasn’t eaten much the last couple of days- this morning was the most I’ve seen her eat recently), but the droppings I did find looked okay (I think?) They were fairly small, solid (no liquid or diarrhea), white with a little brown and green. No blood or anything. No worms.
She hasn’t laid in several months, which I suspect is due to her age. Older hens must go through their own version of menopause, right? I have two other hens who are of the same age; they stopped laying several months ago, too. I think the last time they were laying semi regularly was in the previous spring. When they did lay, it was pretty sporadic- maybe two or three a week, steadily decreasing.
Her breed is a mix between Cochin and buff Orpington. Her diet consists of all-flock pellets, cracked corn (which I mostly give before bed during the winter months to keep them warm, and only as an occasional treat during the warmer months), bugs and plants while free ranging, canned veggies (like corn and peas) once or twice a week, and table scraps (veggies/fruits- often cilantro, tomatoes, raspberries, blueberries, etc. Im aware of the things chickens shouldn’t eat, like avocados and onions). For treats I give them mealworms and cackleberry nugget treats (brand: farmer’s helper). They have water that’s changed regularly and I often add ACV (unfiltered with the mother in it of course) or nutridrench in it when one of them is molting.
She isn’t currently molting. The last time was molting was in late summer; around July/August I would say.
As to whether she’s getting worse, staying the same, or improving? I’d say she’s somewhere between staying the same. Her eating this morning was a slight improvement, although she was only interested in the cooked corn (not the pellets).
Another thing that might be notable is that she’s had a breathing issue for a while. I rescued her and the two other old hens from a neglectful situation about 3 years ago. The coop they used to live in was filthy; extremely dusty, never been cleaned, no ventilation, lack of food and water, etc. They were lucky to make it out alive (many didn’t...there had been at least 15 others and these three were the only ones to make it out). When she began showing symptoms related to this- labored breathing, wheezing, gaping mouth- I was instructed to treat with poultry oxine. Given her background, it was possible she had fungus in her lungs that would slowly suffocate her. Ever since I started treating with oxine, she has improved. Her breathing immediately got better. Whenever it flares up (often at the beginning of the colder months), I use the oxine and it seems to immediately help. Anyways, I’m not sure if that’s related to whatever is going on with her now. Oh- and I’ve treated her twice with permethrin for mites and lice. When I first rescued them, giving them a good dusting before they went into their new home was the first thing I did. Then this past summer we had a case of red mites in our wooden coop. We dusted the whole thing, including the flock, and got rid of them pretty quickly.
I’ve never used a dewormer on them. I bought some Wazine when I first rescued them, in anticipation that they would have worms, but after inspecting them and their droppings, worms didn’t seem to be an issue. So I haven’t used it yet. I check their droppings every now and then for worms and have yet to see any trace of them. I only want to use the Wazine if I find a need to.
Thank you for your help!