Always grateful for the replies BYC. Thank you.
First... (and somewhat unexpectedly), on her breed!
@Phantom_k9 @coach723 @MGG
So Barred Wyandotte's seem to be recognized by the Poultry Club of Great Britain:
https://www.poultryclub.org/breeds/chickens/soft-feather-heavy/wyandotte/
And feature in the UK Wyandotte club:
http://www.wyandotteclub.moonfruit.com/barred/4575722809
We brought her as one... and she looks like those in the photos. But loving the unanticipated confusion. Apologies.
-o0o-
On her health. Thanks all for the comments, even from those of you who are drawing a blank.
@Vickischics. Thank you.
Acities. Build-up of fluid in the abdomen, right? Interesting. The vet didn't seem to think, whatever it is, was especially fluid like. Interestingly, it is also in the less lame leg (the one probably doing more work). The more lame, weaker leg feels totally normal.
You are certainly right about the comb. Pale, maybe even a bit crusty. Not a picture of health. (we'd put it down to age, and the fact she wasn't laying due to age).
If its a cardiac issue, I assume there is nothing we can do, right?
We will keep going with the NSAID and the occasional epsom salt baths.
Again, thanks all.