By far the most important thing is to rest them, no exercise. Some say to starve them for 24 hours at the first signs, I don't......... well not at the first signs anyway. I actually want them to regurgitate their feed for the others to eat, I try to encourage the whole team to go down with it at pretty much the same time. After 3 or 4 days I will fast them for 24hrs, the nest few days they'll be fed light, you'll know when to start feeding heavier and that's when they start tucking into their feed with their wings open. Worse case scenario is if a secondary infection takes hold and then a course of treatment has to be administered. What to treat them for (secondary infection) will differ from loft to loft....... never reach for Baytril, if they need this they wont be worth keeping.