Hi! So in the past I have had chickens that have died from sickness, they were breathing like they were stuffed up in lungs, and they didn't eat, well maybe just a little, but barley, they where loosing their color and looking pale, wasn't sitting up but slouching, and eventually died and it was every three months the same thing would happen to another chicken... But now it hasn't happend in 6 months! I think the disease died off. I did everything I could, their coop was clean, new woodchips, food and crisp clean water, I even gave them vitamins that gives them a boost of vitamin C. They also had sunshine and free roam, but not the ones in the winter, but they did have a warm cozy coop with heat lamps. It made me mad because I did everything right and did everything I could to keep them healthy, but I lost my pets. Now I have beautiful chickens that I do not want anything to kill them. I even have new chickens that are couple months old! I want them to live a long healthy happy life with no sickness!!!!! Is there more I can do to prevent a sickness from entering my flock?!