I have 17 - 8 week old chickens rare and banties breeds mixed, and 3 - 12 week old BR and BO chickens in my flock. They are in their coop our in the barn. About a week ago, I bought new pine shavings from the TSC, and I added about three inches to their bedding (I'm trying the deep little method). Soon after, one chicken started sneezing. I had been using aspen shavings before, and this new pine bedding was a lot dustier than the other, so I figured the chicken was just sneezing. I kept an eye out for the next few days, and checked the chicken, no signs of anything wrong. Last night when I went into the coop, a banty roo was sneezing, along with what I think is a phoenix hen. My 12 week old barred rocks were sneezing too, and one mottled houdan. I spent some time taking a good look, and listening to their breathing. I didn't see any runny discharge from their nostrils at first, eyes look bright and good, but the phoenix hen was wheezing. Then she sneezed and I felt a spray of wetness on my hand, it looks clear. The houdan has some clear discharge in the nostril, but they all act normal and alert. No one seems sick, except for the sneezing. Also, my 12 week BO has diarrhea. It's brown, all liquid, no white. I put Vi-tal in their water and gave them some yogurt. I'm working on putting chicken wire on my dog kennel for a quarantine setup (though I'm worried that the cats will still be able to get to the chickens through the wire). Is it too late to quarantine if they have some sort of infection/virus? Can I treat them with anything or just let it run it's course. Chickens have never been outside since I'm afraid my barn cats will pick them out one by one! One night the door in the coop didn't close right and I lost two chickens (a 9 week old BO, and a 6 week old banty) and came into the coop the next morning to find one of the barn cats sleeping with the chickens! I can't be certain that it was my cats, could have been the tom, but still. Anyway, any help or advice would be appreciated. I really don't want to cull if I don't have to.