Really MissSister? So if your flock lived near a major chicken facility (say, within a mile), you would refuse to euthanize your birds that have a contageous, lethal disease until the birds have given up all will to live, even if it threatens the food supply of the whole nation? Because that's what happened in Cali in 2010 when a small back yard producer (less than 50 birds) had sick birds and refused to cull them. The disease was Newcastle and it spread rapidly across many states, cost billions of dollars, disrupted food supplies and caused thousands of chickens to have to be forceably culled and their carcasses incinerated. Some of those birds were individual's back yard pets.
Your philosophy works great if you have, say, a goldfish. Or an indoor cat. Or something else that never spreads outside your home. Maybe even if you have a house chicken that's never permitted outdoors. But when you purchase even a few hens, you have to understand that you are now responsible for an animal that, if not monitored closely, could disrupt the entire nation's food supply, shut down businesses and cause so much damage to your neighbors that they can no longer provide an income for themselves. Which includes the responsibility of culling sick birds. That occasional sneeze could be a case of Influenza that shuts down the nations food supply. That bird that stumbles a lot could be a case of a resistant strain of Marek's that infects and kill's your neighbors entire stock of rare, endangered, specialty birds. And I would not want someone with sick birds who refused to euthanize them living next door to my flock that I use to feed my family and provide others with a clean, humane food source. Would you want someone who refused to remove their sick birds from their flock living next to your pet chickens?
You also take the responsibility of owning a bird that is prone to reproductive failures (egg binding, prolapse, etc), has very few "perfect" vaccines (as in sterile and non spreading, since many birds still carry and spread what they're vaccinated against), and is on the bottom of the food chain. (Almost all of us loose a bird to one predator or another at some point... And sometimes the predators don't finish the job which means we have to do it for them.) And the best part? Often times there's not even a vet near by who will see them to put them down, let alone a 24/7 emergency vet for those 3-am "oh my god a mink broke into the chicken coop, I didn't even know those lived in my suburb" moments. There's many times that euthanizing is the only humane option.
Incidentally, if your flock gets too out of hand with an infectious disease, the government will come in and deal with it for you. Your flock will be, at a minimum, quarantined under threat of fines and possible jail time. If they deem it to be a real threat to the food supply (say, if your birds have Avian Influenza, pullorum, typhoid, newcastle, etc.) they will come in and seize your birds, even the ones who appear healthy, euthanize them and incinerate them. THAT'S how serious your pet chickens are, and why it's important to recognize that even if they are pets to you they are livestock to the nation. And most chicken diseases spread from local wildlife... The small birds and mice that get into your pen to nibble out of our feeders. And those animals can spread it miles away. Some of the diseases, like AI, even threaten the wildlife itself, killing wild birds enmasse and destroying ecosystems. So even if you have great biosecurity and change clothes every time you go into the chicken pen, your sick pet chickens are still a threat to the nation's food supply and your neighbor's birds and even wild birds. That's the reality of owning an animal that is primarially livestock, even if it's a pet to you.
