My neighbor bought some chickens from someone she didn't know ,. who buys at auctions and resells,. . she did not quarantine. the new birds were sick,.runny nose, coughing, bubble eyes, skinny and weak. I had originally advised Tylan,.. but it's too expensive. She put them on Duramyacin but it isn't clearing it up,.. so I am asking ya'll. She bought some Aureomycin and wants to try it now,.. I am not a big antibiotic user,. so I told her to hold off until I asked some of those that had used it before just giving another antibiotic. Any advise?