I don't worry unless a see a few poops that look abnormal, they stop eating or stop gaining weight, but I'm pretty OCD about weighing them. for example, I have 14 peachicks in brooders righ now and because I weigh them every few days I can predict how much they should weigh on any given day. I did the same with my poults, and it is the best tool to use for spotting illness.
-Kathy
-Kathy