I have made a terrible mistake. I bought 3 hens at a swap Saturday and have infected my perfectly healthy other 6 with something. I don't think it is coryza since they don't smell bad. I noticed yesterday that one of the new ones had a runny nose and one side of her face was swollen and she could barely open her eye. I got her out hoping I might have caught it early. Went to Co-Op today and got Tylan 50 because I figured it is infectious bronchitis. Giving the shot was hard, I would never make it as a nurse. Just went up to check on everybody else and noticed the new buttercup was snotting everywhere and my older RIR is making a weird guttural sound and sneezing. Now I know I have to treat everybody so I put the first sicky back in the coop so she wouldn't have to be in the basement by herself. She looked better before the meds but had bright green poops all day which I think is from not eating much. Here are my questions: 1. I gave the BL 1 cc (or mL) of the Tylan, is that correct for 3 days? It seemed like a lot in the syringe but that is what they said to give. 2. Do I just go ahead and give them all the same dose? 3. Do I need 27 syringes or can I re-use? Just for the record, I know this would be inappropriate for humans, but wasn't sure about them. 4. If it is IB, do they carry it forever like coryza? I guess I'm okay with that since we aren't getting rid of any and don't need more unless these don't make it. We just want eggs. 5. Are they going to be okay? Is this really just the equivalent of a cold or am I looking at some mortality? 6. Is there anything else I need to do? 7. Is there another way to medicate them or can somebody give some pointers on how the give the injection? I'm tired of learning lessons the hard way! Thank you all for all of your information on here and for whoever is able to help!