Also, Lonecowboy made the comment about something to sterilize the dirt. I was told by a lot of people who know to use lime to sterilize the dirt in our barn; you have to rototill it in, and while you're doing that, the chickens can't be in there; the limehas to dissapear. We were a little afraid to try this, and it really wasn't practical for the way our place is laid out,although I'm sure it works. We did, however, soak everything we could reach with Oxine, including misting it on the chickens themselves. I'm sure it helped a lot. I don't know enough about Marek's to know if it would work for that, but I think it might be worth a try, if you want to. Good luck.