I am relatively new to chickens, what I've had before were given to me by my sister so I trusted their health and never had a problem with them. This time I moved to NC and bought 13 pullets from a man, and 2 days later 2 had mucous in their eyes, runny noses, and one you could hear rattling when she breathes. 2 days after that 2 more are sick. 2 days after that 2 more are sick, again. 6 are now sick and are in a horse stall in the barn away from the others outside in their coop and yard. Should I just call it a wash and cull them all, or try to save the still healthy ones? Can you EVER eat their eggs if you give antibiotics? Now that I have sick birds, will the ground around them be infectious, if yes, for how long and can I treat it with something? How likely is it they all will get sick? And is oxytetracycline the drug to use for it, and what's the most recent info on when you can eat or give away their eggs, and where to get the drug? What if dogs or horses come into contact with the chickens or their poop? I'm so discouraged!