What is the longest a chick has had pasty butt? I'm dealing with one that has had it for 3 weeks now. We feed all our chicks medicated mash, poly vi sol in their water and yogurt daily. I also try to keep the brooder at the right temperature. They are 4 weeks now. I feel bad for this little one. It seems to have gotten better but still hasn't gone away. Am I missing something? I heard about people dealing with it for days not weeks.