I've had problems with my flock on and off the last 20 weeks and Im wondering if it has to do with their feed. My flock's issues include: - vitamin defeciency at around 5-6 weeks. They were lethargic, drooped one wing and some even had one leg collapse under them when they tried to stand or walk. They recovered after I gave them some Poly-Vi-Sol (with no iron). - protein defeciency 2 weeks ago, at aout 16-17 weeks. One hen was feather picking and her and a couple others were eating their own feathers. I added yogurt and egg yolk and gave them a homemade flockblock to help keep them enterained just in case they were picking out of boredom. Turns out it was a protein defeciency after all. I have more problems cropping up now but havemt figured out what their cause is yet. Current problems here: https://www.backyardchickens.com/forum/viewtopic.php?pid=7521185#p7521185 I'd love to hear what things youve experienced with Purina.