I am a bit concerned about my 5 hens. They are not eating as much as they did just a few days ago. I have put thier typical stuff out for them to scratch, and most of the day has gone by and they have hardly touched it. They also aren't going through the feeder food either. They are in a run with just enough space ( plan on building a bigger one ). They seem fine in every other way. Laying eggs every day, and energetic, sunbathing,etc. Do I need to worry? What can I do to "entertain" them?