Let me know what you are giving your poults and how much. My poults have come down with something similar to yours, except they sneeze and sound raspy, and the duramycin is not working because they won't drink it. 3 out of my 9 died, and the 6 left have been under quarantine for past few weeks so as to not get my chickens sick. They eat up a storm and will drink plain water, they are NOT lethargic and are still growing (as the little jake is starting to fan and grow his carnucles), but I feel so bad to have them locked up as they are used to free ranging with the crowd. I have found all kinds of sicknesses that it could be, but none have matched 100%. We did have rainy cool weather just before they got ill and I am wondering if they have pneumonia??? Let me know how it is going for you...thanks, Donna