About a month ago, we treated our flock for coccidiosis based one several bloody poops. They all got 1 week of treatment. No bloody poops for a few days then noticed it again. We then figured out which chicken was still sick and culled her (since she was much worse even after treatment and wanted to save the flock). We treated them all again for 5-7 days after she was gone. Now 2 weeks have gone by and all of that flock seem great. They have a huge coop, huge outside run, and seem fine. Today we see this in the coop. Note: Some of the oldest ones are nearing laying age. Thoughts?????