I've got a bunch of chicks and older chickens that seem to be a bit sick. One silkie sounds kind of flemmy, has sounded this way for about a week, maybe getting a little better. He's about 4 months old, I have a heat lamp in the coop. There are probably about 15 others that are shaking their heads, the ages range from 1 week to a year. It has been going on for about a week and a half. I haven't seen any other symptoms other than an occasional sneeze. Our weather just turned rainy, mucky and cold about a month ago. If I treated them with some antibiotics, would that help? What kind would be best? I've been giving them some apple cider vinegar in their water, they all got some vitamin drops in too but I phased that out a couple days ago. I'd like to get rid of this bug as soon as possible. I'm ready to have healthy chickens!! Thanks!