This has been an interesting topic to read so far. Lots of individuals with well thought out opinions. Ah, the miracles of modern medicines and antibiotics that has helped so many. Yet the overuse of said antibiotics also causing equal harm. Not to mention which one to use for which illness(es) and were they diagnosed correctly to begin with before administering.
I live in the heart of commercial chicken and turkey houses. I have a chicken house not 200 feet from my front porch. Thank goodness that they stopped raising chickens in 2001 and now only use it for storing hay. But I was able to see first hand and on a daily bases how chickens where raised. The unnatural rate of growth from the steroids and antibiotics in their feed. One somehow made it out of the house and into my yard. The owner said I could keep it. It was only 2 days old and therefore had only 2 days of the medicated feed. I watched it grow way too fast (twice the size of my month old RIR in a matter of weeks) and then a few months later collapse and die from underdeveloped lungs. Its excessive growth rate and week legs caused suffocation. All from just two days of antibiotics and steroids. This is why I'm an advocate for organic methods.
I prefer the organic (antibiotic free) route. But would consider antibiotics in a true emergency when I know the animal could be saved. Otherwise, it would be best to cull if the chances were 50/50 and it wasn't a prized bird or main brooder. It's a tough choice no matter whether your pro or con on antibiotics.
Then like so many others I live in the country and have two vets that treat livestock and pets but not birds. They also won't give or prescribe any meds without seeing the animal and since they don't see birds... you get the point. So we are left to our own devices. Thank goodness we do have an internet with vast amounts of information. The trouble is one symptom can be any number of things so you have to narrow it down by treating with trial and error until something finally works. Not to mention that there is equal number of misinformation out there. Frustrating indeed.
But what did they do 100 years ago when there were no antibiotics? Sure there was penicillin, but did they give it to the livestock? My thoughts (theory) are that they may have treated with natural medicines and herbs. My goal, especially in light of this news, is to research as many foods and herbs that are safe for the birds to eat and what properties the herbs give (example: oregano as a natural anti-bacterial, flax seed as a natural anti-inflammatory, etc.) and make a list. Then treat the birds based on symptoms by trial and error. Yet, it's important to treat with one thing at a time so you can find out what works. That way when you see these symptoms again you can use the method that worked immediately with less trial and error. And yes, it may be more difficult than it sounds.
There are diseases out there that natural medicine will never help. It is at that point that the tough decisions will need to be made (antibiotics if available or cull).
As always I am open to the suggestions of others who may have experienced and successfully treated what issues are new to me. Thank goodness for forums like this one for those who do not have access to experienced vets and others who have raised birds for years/decades in their area.
You can only do the best you can. It's just a shame that there are so few resources (i.e. vet's) available when help is needed.
Just my two cents to the topic