Some of my hens sound like they have a cold, snotty and sneezing. they are almost all a year old. The eat laying crumbles. free range on an acre, they seem bright, clear and eating,free ranging. No one is dripping anything just seem snotty sounding. We have had crazy weather hot then frezzing and the wind has been blowing, the weather changes everyday. Is there anything I sould be doing. Everyone is acting fine just sound stuffy, should I worry. I hate to treat with anything unless I knowI have a problem??but I am at a loss.