All five of my 15 week old Barred Rocks have suddenly stopped eating for the past two days. Temps have been 10-15F warmer than previously. I though maybe their fermented feed went bad due to the temp increase, so I threw it out and made a new batch. In the meantime I gave them dry feed, but they haven't touched it either. What could be wrong? ETA: They appear to be still going after insects that make it into the run & what little vegetation that remains; but no feed.