For the last week my rooster (copper maran) has been sick. He barley moves and he falls asleep a lot constantly, he wont even look up for loud noises. Then he developed a rattling in his chest that is extremely audible even from several feet away. Then my baby milly fluer got it yesterday and died later last night. When i went into the pen this morning all of my roosters, and my buff orpington hen have bad rattling in their chest. It sounds like theres a fluid in their lungs. The others that just got it are starting to become lethargic too. Duramycin isnt working and we have several young chicks and tukeys im using for fair that i dont want to die like the milly. Would Tylan 50 work? also i run a pigeon breeding buisness and have brand new squabs. Could the sickness effect them? The chickens dont have puffy eyes, blotchy skin, or runny noses and they dont sneeze, they just sleep a lot and have rattles in their chest. any idea what it is?