Sounds like you have one of the respiratory infections going on in your flock - you mentioned the bird in the house smells bad, is it a foul odor of the "breath" -- can you check the other birds for a similar odor? What specific antibiotic are you using and at what dosage? Is there any bubbling in the eyes? How many days has it been since they started showing symptoms? How old are the birds? Did you recently add any new birds to the group?
I did just add a new bird she's actually doing better than the rest I'm using terra vet 10 tetracycline hydrochloride soluble powder and vet rx the others don't smell bad or have the raw spots under the wings this started about a week ago we still have mosquitos here in east Texas with all the rain they are about 14 months old
How long ago did the new bird come in and did you do a quarantine prior to integrating her into the flock or move her right in? There is a very good chance that she is a carrier and has introduced the illness to the rest of the flock.
Its name is Aureomycin 4G Medicated crumble. I hope everything works out with yours and makes your feel like their old selvestoo!
30 days is usually the quarantine period for new birds. I don't use these products; tetracycline, aureomycine, tylan, vet rx, or baytrill to try to medicate sick birds. they will always be carriers, even if they show improvement. I use the hatchet method. I only breed birds that have never been sick, sometimes waiting up to 2 years to breed a hen. this insures longevity and disease resistance in the flock