Ok, I have 4 pens of chickens. Laying hens, big kids (6-8 weeks), little kids (4 weeks), and babies (5 days.) The big kids have coryza. I've made the decision to cull them all tonight, even though only 6 of the 8 are showing symptoms. So my question is... do I give Sulmet to the other chickens as a preventative measure, or do I wait for symptoms? Can I give Sulmet to the babies? All 4 groups are kept in their own little worlds, though they're close enough to share the same air. The little kids have been in a brooder that the big kids used, up until I started seeing symptoms in the big kids. So far, nobody else has symptoms. So I've made the decision to cut my losses with the big kids. But what do I do with the others? Wait and see? Or give everyone Sulmet and throw away the eggs for awhile?