Good Morning Friends! I've had an ongoing respiratory thing going around in my coop (sneezing, mucus flinging, eyes sealed shut). After treating with a broad spectrum antibiotic in the water and fogging with Oxine (neither of which worked), I thought I finally got rid of it with a round of Denegard. Everyone got better except for one chicken who continued to occasionally sneeze and another chicken whose sealed shut eye took forever to get unglued. Finally, when the sealed eye started to open, and the sneezes seemed to subside, one of my pullets started sneezing and shaking mucus all over the place. I immediately removed the pullet from the coop and started nebulizing her with Oxine. The next day, while nebulizing her, when she opened her mouth I could see that it was filled with mucus, AND another pullet's eye is sealed shut. I decided to get some Tylan 50 injectable. I will give the Tylan 50 to: the sick pullet with mucus the pullet with the sealed eye the hen who never completely stopped sneezing, and I think to the hen whose eye took forever to unseal. MY QUESTION IS THIS: I have a total of 16 chickens (chicks, pullets, and hens). Should I treat them all and just kill this thing? Should I just treat all the hens and the sick pullets? Should I give everyone just one dosage and give the symptomatic birds the full 3-day treatment? Are there dangers to giving a one-day treatment of Tylan 50 to non-symptomatic birds? What would you do? Thanks!