Hey, I have 4 laying hens around 8 months old. For stone reason they haven't ate any feed the last 2days. When I let them out they eat grass and bugs like they're starving but there feed is still full. They have grit and get some scraps. The only change is we have started giving them some corn now that the weather's getting cold but they aren't really eating that either. Any advice? I thought they would eat more with the cold weather?