This is my first year with chickens so I'm in need of a little experienced advise. I have 8, 10 wk old pullets and 23, four week old cornish x's. The cornish X's have a vitamin supplement added to their water per the instructions on the hatchery's web site. They eat a 20% protein starter/grower, non medicated although for the first two weeks the chicks got medicated feed. I've noticed and occasional sneeze in the flock, may one or two sneezes while I'm out feeding (1/2 hour). This has been going on for about a week. No other signs. No runny noses, no coughing, no eye discharge, everybody looks healthy and happy, eating well, poop looks normal but they have access to a large grass area so its a little hard to tell. Maybe a slight increase in the sneezes. The older pullets are in a separate are but are close to the chicks. Both groups have access to grass, they both have shelter, but are not confined inside during the day. The weather has been impossible, 90's and humid, followed by 70's and raining, then windy and cool, more rain, heat, you get the idea. I've had the heat lamp on for the chicks at night, but at least one night the ground was damp in their tractor in the morning. I've been watching them closely, and still do not see any symptoms other than the occasional sneeze. I am attributing this to the damp conditions and other weather stress. Unless I see other symptoms or the sneezing increases I was not planning on treating the chicks with antibiotics. Does this course of action seem OK? I hate to give them antibiotics if they really don't need them, but I don't want to wait if it might compromise their health. Thanks!