I have raised/been around chicken my entire life. Lately, I have had some issues. We raised 15 buff orpingtons, along with 50 meat chickens. Butchered the meat birds and continued to care for the orpingtons. We got them March 23, 2016. The orpingtons ar not laying yet. They also seem to be getting sick. Four have swollen eyes, which are closed entirely, One was very sneezy and rattled. I started putting tetracycline in their water. They seemed to be getting better. The other day, the worst one took two drinks, arched her neck, squacked a noise I had never heard from a chicken before, flopped an her back, flapped her wings, and died right there. I have since lost three more, but these were not showing any other cold-like symptoms. I should also mention that I purchased ten 12 week old pullets 3 weeks ago that appeared very healthy and came from a very clean and healthy environment, I also purchased 15 pullets from a free range farmer in July. They get well water (water tested every year), cracked corn, and a little laying mash and protein, There are let out into a pen during the day, shut up at night, and let out to roam the yard now that flowers and garden are done. No pesticide use.