I have 7 chickens, I just bought 4 new ones. One hen began coughing then sneezing, very few tiny filthy ugly eggs,like a raspy cough, tonight bubbly eye and coughing huge clots of blood ALL OVER THE WALL. I culled her. I have had them for 4 weeks. So if the others start the same should I dispose the whole flock and give up? I have raised pigeons for years and I dont want to infect them.