I have four hens, two Buff Orpingtons and two Barred Rocks, about a year old, and in great health. Up until this week they've been laying very well, but suddenly, they've gone on strike. NO eggs for a few days! What could be the problem? Is this normal? They're not acting broody, and I'm not seeing tons of feathers, like they're molting. They're all acting, eating, pooping normally, just not laying eggs. What can I do to get the production up?