Okay, hmm...
Is his tail droopy? What color is his comb right now?
I am sorry if I am no help,
but try not to give him
too many medicinal things (if you did, that is.)
Stay organic.
You once wrote in one of my threads about the vinegar in water,
are you still doing that? When one of my hens took sick, I put calcium in her water.
(The oyster shells) She was fine, I stopped, thinking she was fine, no more calcium, she passed away. Try to continue either; thyme, vinegar, calcium even oregano.
I would never use my birds for meat, some people use oregano for those birds.
I guess if it helps them for meat, it can for eggs!
Good luck! I hope all goes right!
-The Angry Hen