help pls, unwell and really fed up Legbar

[Calm]

Morning All

I have an unwell Leg bar, had her for over a year not sure of her age, but she looks as though she is getting on, up to 2 weeks ago she was laying eggs and eating ok, but
she then started laying eggs with no shells, often the shell less eggs would just bust and come out where ever she was, around the garden all the birds are free to roam around the garden during the day, they feed on the grass, there is lots of grit and oyster shells for them, have over 20 hens all others are laying and eating fine,
over the last week she has gone off her food, I give them layers mash in the mornings and maybe some pellets or sometimes corn in the afternoons, fresh water each day, I felt her crop last night its about the size of half of a tennis ball and watery, not much food in there,

Yesterday and this morning she has eaten a small amount at breakfast then just sits there, with her eyes closed, she may go and sit in the nesting box for a bit as if to lay an egg, but she is not laying any eggs, she is or was high in the pecking order if fact best mates with the top bird, I got them together, her feathers look washed out, have just looked at her now and her vent looks as if its pouting, she is looking for a nesting box to sit in, I have 3 broody hens, she is not broody, but really fed up and cheesed off, have a gut feeling she is going to die unless I can pin point her problem, I keep watching to look at her poop but haven't seen her go lately, I have noticed some of the other birds have slight runny noses and have watery pooh, I have 12 young at the moment, they live in the same coop and even some of them have runny noses too, not sure if this connected, any help will be welcome Thank-you

 

[realsis]

Does her abdomen appear swollen or hot? Does their appear to be.extra fluid in the abdomen? If so she could be laying internally? Also you mentioned. Some chickens have a runny nose
That's a sign of upper respiratory illness. Perhaps. she is.commimg down with that? Check her over real well listen to. her breathing
Is there. Any.mucus.present? Sneezing or cough? If you don't think. Its a reproductive issue then I might consider treating for. Respiratory. But first try and rule out.any possible reproductive issues
Hope this helps. Best wished

 

[Calm]

Realsis

Thank-you so much for your help, her abdomen feels normal, and yes there was extra fluid in there when I put up this notice for help,
I have checked her all over for any clues, breathing seems fine, no cough or sneezing,

her muscles are soft but then she has been doing nothing for over a week now, last 3 days just sitting in the shade
her pooh is watery and clear mostly, maybe a tiny bit of white solid,
her eyes don't seem to be right,
she has a large comb over the right eye which she has open at times
but the left eye is closed, its not swollen, its like the day light is a problem for her, when the eyes are open the pupils are large

and very quickly fluctuate between smaller and large pupils , there may be some slight cloudiness in the eyes

I know its hard to diagnose someone else's issues when you cant see the bird, but if you have any ideas, I will be Thank full