To help us better help you, could you possibly answer the questions from the below-listed sticky post - only answer them into *this* thread so that we can read them? This helps us to establish a flock and bird history. The more information you provide, the more accurately we can help you. If you'd like to provide more, please do! You can't give us too much information really. Again the more you provide about every aspect of this chicken, the flock, the environment, the better.
https://www.backyardchickens.com/forum/viewtopic.php?id=3569 <-- the sticky thread.
Also, I'd recommend highly that you pick this old wonderful boy up and examine him thoroughly for mites/lice. Do at least a couple of checks during the week at night as mites don't always stay on the bird; they spend most of their time off the bird and only come back on to feed.
Check carefully in the warm/moist areas and very thoroughly as both are hard to see and are very very tiny. Good areas to concentrate are under the wings - all in the feathers as well as the body, around the back of the neck, and around the vent. Be sure to look for lice eggs clustered around feather bases. To me, they look sometimes like miniature snow. But any white clusters will be lice eggs.
If you find any, you must treat both bird and premises. Let us know your findings and we'll tell you how.
Also, please be sure to tell us details about his roosting arrangements, what ground you have (soil, grass, sand), the bedding in the coop area (kiln or regular pine shavings, cedar, etc), what he's eating specifically and how much of each, etc.
As for pneumonia, most likely he had another respiratory illness. If he shows symptoms of that, and the treatment was successful, consider doing that again. Often the symptoms disappear but birds can remain a carrier, falling prey to relapses in stress conditions.
I'm glad to hear that he eats well, and he sounds like he's received wonderful care! I'd like to see a few more years tacked onto his life span before he heads off elsewhere.
Hopefully we can help you with that.
Thank you!
P.s. on his breast, check carefully for any breaks in the skin and treat with an antibiotic ointment like plain old Neosporin. No cortisone in it, no 'caines or pain killers - just the old fashioned neosporin triple antibiotic. The skin is the bird's number one defense against illness and so we don't want it broken. Be sure also that where ever he's resting is very very dry, perhaps kiln-dried or compacted pine or aspen shavings like you find (less expensively) at the feed store for horses. If he's on dirt, consider using some play-sand or other dry and very course (not fine) sand to dry up the area so that the dampness is cleared a bit.
What antibiotics did you use previously? What were his symptoms?
